EMX or EMK POWER SUPPLY

INSTRUCTION MANUAL FOR EMX or EMK POWER SUPPLY LAMBDA EMI 405 ESSEX ROAD, NEPTUNE, N.J. 07753 Tel: (732) 922-9300 Fax: (732) 922-9334 Web: www.lambda-emi.com

ONE-YEAR WARRANTY Electronics Measurements, In warrants this equipment manufactured by us and sold by us or our authorized agents to a manufacturer or end user to be free from defects in material or workmanship. Our liability under this warranty is limited to servicing and repair or replacement of parts when equipment is returned to us with transportation charges prepaid within a period of one year after original shipment and when the equipment is shown by our inspection to be thus defective, normal wear and tear excepted. This warranty does not apply to equipment subjected to abuse or incorrect installation or operation, nor to equipment repaired or modified outside of the Electronic Measurements, In factory unless prior written approval to make such repairs or modifications has been received from the factory. The foregoing warranty is in lieu of all other express or implied warranties except of title. CAUTION While this supply is designed for safe operation, certain precautions must be observed. This unit is intended to be operated by technically competent personnel generally familiar with the principles of electrical safety. Whenever the AC power supply circuit is energized there are EXPOSED LETHAL VOLTAGES within the enclosure. Hence, the supply circuit must be turned off by unplugging the unit or, in the case of hard wired units to the power source, removing the line fuses or securing the breaker supplying the unit before attempting any operation requiring entry. Remember that even after the line is disconnected, energy can still be stored in capacitors and such unexpected places as the interwinding capacitance of transformers. The input, output and sensing terminals of the supply are potentially hazardous. These risks are not always obvious. Most people are aware of the dangers inherent in high voltage equipment. However, available energy of a 5 volt supply are not usually thought of as dangerous. In addition to the steady state energy available, such supplies are typically terminated by very large capacitors, which can deliver huge surge currents. Consider what could happen if a ring, wrist watch, or other metallic object attached to a person were to short across the output of such a device. High current supplies are capable of vaporizing metallic objects, such as screwdrivers. This can result in molten metal being sprayed on people. EXERCISE EXTREME CAUTION WHEN USING THESE SUPPLIES

ELECTRICAL STANDARDS All company primary standards are either certified directly or are traceable to certification by the National Institute of Standards and Technology. CLAIM FOR DAMAGE IN SHIPMENT This instrument received comprehensive mechanical and electrical inspection before shipment. Immediately upon receipt from the carrier, and before operation, this instrument should be inspected visually for damage caused in shipment. If such inspection reveals internal or external damage in any way, a claim should be filed with carrier. A full report of damage should be obtained by the claim agent and this report should be forwarded to us. We will then advise you of the disposition to be made of the equipment and arrange for repair or replacement. When referring to this equipment, always include the model and serial numbers. RETURNING EQUIPMENT Before returning any equipment to the factory, the following steps should be taken. 1. Notify Electronic Measurements, In, at 908-922-9300. Give a full description of the difficulty, including the model and serial number of the unit in question. Upon receipt of this information, we will assign a Return Material Authorization number (RMA) and give you shipping instructions. 2. Equipment returned to us must be packed in a manner to reach us without damage. The shipping container must be marked with the RMA number in an area approximate to the shipping label with numbers that are easily read. All returned units that do not show the RMA number on the outside of the container will be refused. 3. For non-warranty repairs, we will submit a cost estimate for your approval prior to proceeding.

EMX or EMK OPERATING SYSTEM MANUAL TABLE OF CONTENTS I GENERAL INFORMATION 1.1 DESCRIPTION 1.2 SPECIFICATIONS II INSTALLATION 2.1 INSPECTION 2.2 INSTALLATION 2.3 POWER REQUIREMENTS 2.4 PANEL AND REMOTE CONTROLS 2.5 CIRCUIT PROTECTION 2.6 ACCESSORY III OPERATION 3.1 BASIC OPERATING PROCEDURE 3.2 PROGRAMMING (REMOTE CURRENT CONTROL) 3.3 OVERCURRENT KILL CIRCUIT IV THEORY OF OPERATION 4.1 GENERAL 4.2 POWER CHANNEL 4.3 A100 PC BOARD 4.4 HIGH VOLTAGE IGNITER V MAINTENANCE 5.1 PARTS REPLACEMENT 5.2 TEST ANDCALIBRATION PROCEDURE VI TROUBLESHOOTING 6.1 A100 TROUBLESHOOTING PROCEDURE 6.2 TROUBLESHOOTING CHART MEMORANDUM TO USERS OF EM POWER SUPPLIES IN RACK INSTALLATIONS

All EMI power supplies have been designed and tested to provide full rated current and voltage throughout the specified line voltage range at the rated ambient air temperature. To achieve this maximum rating, airflow as provided by the internal fans, proportioned and directed by chassis openings and internal partitions, must not be impeded. It is not required but is desirable to prevent blocking air openings on the top of the supply. On 3φ supplies air enters the unit on the right-hand side at the location of the fans and is transferred through the supply in a horizontal direction toward the left. Airflow is reduced any time there is a negative pressure at the air inlet or positive pressure at the air outlet. Each fan is capable of providing 100 to 130 cubic feet per minute of airflow (CFM at zero static pressure. The supply itself produces some restrictions to this flow so that approximately 80% of the airflow is available. As static pressure increases, caused by additional restriction of airflow external to the power supply, the efficiency of the fans drops significantly and airflow is greatly reduced. This reduction in airflow causes a substantial increase in internal temperatures of the supply, frequent thermostat shut-down and reduced power supply reliability. On 1φ TCR power supplies, air enters the sides of the power supply and is exhausted out the rear. On the EMS series air enters the unit by means of slots in the front panel and along the sides and exits primarily from the rear. The same airflow considerations as previously discussed are still applicable. Ideally when power supplies are mounted in a rack, the rack should have no sides or rear covers. Since this is usually not practical or safe, the installer must consider the effect of any enclosure on power supply airflow. Since the power supplies are heavy they must be supported by some sort of rail along the sides of the supply, front to rear. This rail must be chosen for proper strength but must not be either too close to or extend up too far along the side of the supply or airflow will be blocked. To minimize vertical height use an angle iron of substantial cross section and unequal leg dimension. Do not support the power supply from the front panel only in an attempt to minimize this problem. The rail does not need to be continuous from front to back to support the supply but for safety and ease of installing and removing the supply it usually is. Most commercial racks are available with louvered side panels and doors. Side panels are also available with an extended depth which provides an additional plenum space on each side of the rack for improved airflow. Burn-in systems impose two additional considerations for power supply installation. The supply rack is often placed next to the oven and is sometimes integral with the oven. The thermal insulating qualities of the oven both through conduction, convection and radiation can impart substantial heat to the power supply rack and subsequently to the power supplies. If it is possible, separate the supply rack from the oven by a combination of space, insulation, reflective surfaces or moving air. The ambient in burn-in rooms, especially in tropical climates can also be very hot. Frequently high humidity is also present. This situation, while not ideal for power supply longevity, should

itself cause little difficulty. When combined with insufficient airflow, however, it can significantly affect power supply reliability and the usable output current capability of the power supply. The rack must exchange with ambient temperature air the same number of CFM as the power supplies circulate or the power supply exhaust air will be recirculated many times resulting in a continuously rising temperature until some elevated thermal equilibrium is reached. Each 3 1/3" fan in the system transfers 40 CFM while each 4 5/8" fan moves as much as 140 CFM. Air must be exchanged from outside to inside to outside the rack at a CFM value equal to the sum of the CFM ratings of all of the fans in all of the power supplies. In addition this transfer must be accomplished in such a way as to not impede each power supplies' internal airflow. When figuring out how to accomplish this is in any given installation consider any action which would tend to increase air pressure at air outlet points is beneficial to supply cooling.

I GENERAL INFORMATION I.1 DESCRIPTION The EMX/EMK series power supply is a completely solid-state regulated current source with a continuously variable output, designated particularly for supplying power to xenon or krypton arc lamps. Stable light output and long lamp life are ensured since the lamp current is regulated to within 1% regardless of line functions and the ripple current is less than 2%. the semiconductor circuitry allows instant start-up and the use of silicon controlled rectifiers as regulating elements provides high reliability and high efficiency in a very compact unit. This power supply also provides the boost or "open circuit" voltage required for starting arc lamps. In addition, it can pulse any standard igniter to permit a completely automated starting sequence, locally or remotely controlled. The EMKI series power supply incorporates a built-in high-voltage igniter assembly which is pulsed automatically when the power supply is turned on. I.2 SPECIFICATIONS I.2.1 input Three-phase, three-wire system, (plus neutral for 380V operation). Line Voltage, phase-to-phase: Line Frequency: Line Current: 188-242V or 342-418V (See schematic). 47-63Hz (57-63Hz for units rated over 10kW). 1.6kW - 8A 3.5kW - 15A 6kW - 25A 11kW - 43A NOTE: Current ratings of line fuses in some models may be lower than rated line current because of internal circuit arrangement. Be careful to replace fuses only with the type specified on the fuse cover plate or on the schemati I.2.2 output MODEL BOOST (V) OPERATING (V)* CURRENT (A) EMX28-75 120 28 75 EMX35-100 120 35 100 EMX40-165 120 40 165 EMX75-140 120 75 140 EMK120-50 350 120 50 EMK150-40 350 150 40 Page 1 of 21

EMK200-30 EMK200-40 EMK220-50 EMK240-25 375 375 375 375 200 200 220 240 30 40 50 25 *Guaranteed minimum value at lowest specified line voltage. High voltage ignition pulse (EMKI units only): Single Lamp Models 20kV Dual Lamp Models 30kV Super Igniter Models 50kV Ignition pulse amplitude values are approximate. Actual value depends on load characteristics and distributed impedances of load leads. I.2.3 general Current Regulation: 1% line and load combined, over useful operating range of lamp(s) (50-100% of rated current). Current Ripple (RMS): Less than 1% for EMK units and less than 2% for EMX units. Ripple is measured with lamp(s) ignited and the power supply operating between 50-100% of rated current. Dynamic impedance of the lamp(s) is to be greater than 0.9Ω per lamp for EMK units and greater than 0.1Ω for EMX units. Temperature Coefficient: 0.02% per C. Stability: 0.1% for 8 hours after warm-up, under fixed line, load and temperature conditions. Response Time: Approximately 25mS for a 30-100% current programming change. Ambient Temperature: Operating: 0 C to 50 C. Non-Operating: -40 C to 85 C. Protection: Fuses or circuit breaker for input lines. Fuses for auxiliary circuits. Automatic reset over-temperature switch de-energizes line contactor. Adjustable over-current kill circuit drops output to zero in case current regulation goes out of control. Auxiliary contact on line contactor discharges filter capacitors when unit is turned off. (Except output capacitor on super igniter units). Page 2 of 21

Size: All units: 19" (483 mm) rack width X 20" (508 mm) depth + 2" (51 mm) for output terminals on EMKI units. Panel Height: EMX28-75, EMX35-100: All others: Weight: EMX28-75, EMX35-100: EMX75-140, EMK: EMKI: 7" (178 mm). 8 3/4" (222 mm). 135 Lbs. (61.4 kg). 180 Lbs. (81.8 kg). 215 Lbs. (97.7 kg). II INSTALLATION II.1 INSPECTION Immediately after unpacking the power supply, perform a visual inspection for possible internal and external damage incurred in shipment. If such damage is found, follow the "Claim for Damage in Shipment" instructions printed inside the front cover of this manual. II.2 II.3 II.4 INSTALLATION Refer to Section 1.2 for dimensions and other general information. Before placing the power supply in operation, see that all packing material has been removed. On EMKI units, remove the output terminal guard and reinstall the three mounting screws and washers into the cabinet. Save this guard together with all other packing materials in the event that the unit is reshipped. Make sure that adjacent equipment does not block the air intake or exhaust openings. Except for test purposes, this unit should not be operated with covers removed. For electrical installation requirements, see Sections 2.3 and 2.6. POWER REQUIREMENTS This power supply requires a three-phase input, of the specified voltage phase-to-phase (three wire system). For 380V operation, a common return to neutral is required (four wire system). Unless otherwise specified, units are supplied strapped for 208-220V operation. For 380V, jumpers can be changed with a screwdriver (see Schematic). Phase rotation sequence of the input lines need not be observed. PANEL and REMOTE CONTROLS The following panel controls are provided: Power switch with indicator, or circuit breaker (optional). Continuously variable output current control. Ammeter. d. Voltmeter. Page 3 of 21

e. Elapsed time meter (optional). The following remote control functions are provided: Turn-on and/or interlock. Current metering. Elapsed time meter. d. Current control of programming. e. Pulsed power for 120V or 230V igniters (optional, EMX only). f. High-voltage igniter disabling interlock (EMKI only). II.5 CIRCUIT PROTECTION The three AC input lines are protected by fuses or an optional circuit breaker and the internal control circuits are fuse protected. Fuses are accessible by removing a cover plate at the rear of the unit. On EMKI units, the high-voltage igniter circuit is protected by a fuse mounted on the igniter circuit board. CAUTION: On EMKI units, all wiring between the POS (IGNITER) terminal and the lamp should be insulated to withstand at least 75kV. Load leads should interfere with operation of the igniter. II.6 ACCESSORY II.6.1 Programming (remote current control) Remove the jumper between terminals TB3-10 and TB3-11. Connect a variable resistor (rheostat) as follows: wiper and clockwise end of resistance to terminal TB3-11. For operating information, see Section 3.2. NOTE: Connections between the power supply and the remote control point should be made using shielded wire having an insulating jacket. The shield be grounded at one end only by connecting it to terminal TB3-9. II.6.2 Igniter (EMX units only) Connect the primary side of the igniter to terminals TB2-6 and TB2-7 if 115VAC operated, or TB2-7 and TB2-8 for 230VAC. II.6.3 Turn-on and/or interlock Remove the jumper between terminals TB3-16 and TB3-17. With Power Switch or circuit breaker on, the unit can be turned on and off remotely connecting a switch between these terminals. A cooling or other interlock may also be connected in series with these terminals. Page 4 of 21

II.6.4 Elapsed time meter An external elapsed time meter (220VAC only) may be connected to terminals TB3-14 and TB3-15. These terminals are energized whenever the unit is turned on. II.6.5 current metering An external may be connected to terminals TB3-12 and TB3-13 to monitor the DC output current. The power supply produced approximately 50mV at these terminals when delivering maximum rated output current. It is recommended that a meter of greater sensitivity having a calibrating resistor in series be used to compensate for internal tolerance and the IR drop of the meter leads. WARNING: On "transformerless" units, (without T1), output and auxiliary terminals are NOT isolated from the input line. All terminals and external circuitry (including NEG output) must be insulated from ground to withstand line voltage. GRD terminal (TB1-5) MUST be earth grounded. III OPERATION III.1 BASIC OPERATING PROCEDURE WARNING: Lethal voltages are present at various terminals of the rear of this unit. On EMKI units, extreme caution should be observed regarding any connections associated with the high-voltage igniter or lamp circuits. On super igniter units (for use ILC lamps), dangerous voltage remains at the output terminals for several minutes after the power is turned off. For safety during servicing or maintenance, short circuit the POS and NEG output terminals momentarily, after the unit has been turned off. Be sure the POWER switch or circuit breaker is off before making the necessary electrical connections as described in Section 2.6. CAUTION: In order to avoid damage to the power supply, do not operate EMKI units without a load unless the high voltage igniter is disabled by removing the jumper between terminals TB3-18 and TB3-19. Set the CURRENT control for approximately the desired output current. Turn the POWER switch or circuit breaker on. For resistive loads, the ammeter should be read approximately the current set on the CURRENT control. In arc lamp applications, the igniter automatically pulses at intervals of several seconds when the power supply is turned on. If the lamp fails to ignite after a period of about 20 seconds, power is automatically removed from the POWER switch or circuit breaker for five seconds then turn it on again. When the lamp ignites, the ammeter should read approximately the current set on the CURRENT control. The CURRENT control may now be used to set the output current to the exact value desired. III.2 PROGRAMMING (REMOTE CURRENT CONTROL) The output current can be remotely controlled by a variable resistance as follows: Page 5 of 21

Connect the remote programming resistance as described in Section 2.3.1. Follow the operating procedure in Section 3.1. However, the front panel CURRENT Control is now disabled and all references to the "CURRENT control" therefore apply to the programming resistance. III.3 OVERCURRENT KILL CIRCUIT In the event of a malfunction in either the power supply or the remote control circuitry which causes an excessive or uncontrolled rise in output current, the overcurrent kill circuit will automatically cause the output to drop to zero. To reset the overcurrent kill circuit, turn off the POWER switch or circuit breaker then turn it on again. If the overcurrent kill circuit trips again, refer to SYMPTOM 13 in the Troubleshooting Table. IV THEORY OF OPERATION IV.1 GENERAL Major functional sections of this power supply include: silicon controlled rectifiers (SCRs) as the rectifying and regulating elements, a main power transformer (T1) (if so equipped), a choke-input, L-section output filtering circuit, a current sensing shunt (R3), a CURRENT CONTROL (R4), an auxiliary power transformer (T2), a control and ignition sequencer printed circuit board (A100), and a high-voltage igniter assembly (if so equipped). A block diagram of the power supply is shown in Figure 4-1. Page 6 of 21

IV.2 POWER CHANNEL Input power is applied through the contacts of power relay K1 and through fuses F1-F3 or circuit breaker CB1 to the primary side of power transformer T1 (if so equipped). The secondary side of T1 is connected to six SCRs in either a bridge or a full-wave configuration, depending upon the model (see Schematic). The SCRs act not only as rectifiers, but also as current regulators in the following way: If each SCR is triggered just when its phase voltage crosses the zero axis, the combined output voltage waveform will be that of a conventional full-wave rectifier. However, if the trigger pulse to the gate of each output voltage waveform will be missing and after filtering the L-section filter (L1, C1, et) the resultant DC voltage output will be Page 7 of 21

lower. By varying the trigger pulse delay time in response to a signal from the current-sensing resistance R3, regulation of the output current can be achieved. The voltage drop across R3 is also used to provide an indication of output current on the front panel ammeter. The additional components associated with the SCRs (see Schematic) serve the following purposes: C20 through C25 provide noise suppression at the gate of each SCR to prevent false triggering. R20 through R25, connected between gate and cathode of each SCR, provide a leakage path and a more constant load impedance for the gate drive signal source. The RC snubber networks, connected between anode and cathode of each SCR, round off the leading edge of the AC voltage waveforms to prevent the SCRs from triggering prematurely from excessive rate of rise of anode to cathode voltage. Resistors R30 through R32 assure proper starting by providing shunt paths around the negative SCRs at a time when such a path is required and a trigger pulse is not present. Transformer T2 supplies AC voltage for the auxiliary power supply on the A100 PC board as well as a portion of the AC voltage required for the boost regulator. IV.3 A100 PC BOARD The control center of the power supply is the A100 PC board. The major sub-circuits contained on this board include: The auxiliary power supply, the current amplifier, the over-current kill circuitry, the phasing transformer, the SCR firing circuitry, the boost regulator, the igniter trigger and the sequence and timing circuit. IV.3.1 auxiliary power supply The auxiliary power supply provides + and - 15VDC regulated for all circuitry on the A100 PC board. The positive output is regulated by the series-pass transistor Q401 whose reference voltage is derived from diodes CR402 through CR404. The negative output is regulated by zener diodes CR405 and CR406, and resistor R402. IV.3.2 current amplifier (regulator) Current regulation is achieved by comparing an adjustable reference voltage to the voltage drop across a shunt produced by lamp current flowing through it. The difference is amplified, and the resultant error is applied to the SCR firing circuit so that the lamp current produced by the SCRs tends to reduce the error signal to zero. The reference voltage is derived from zener diode CR301, and adjusted by R302 and R303 to provide a 50mV level at one input of IC301, when CURRENT control R4 is fully clockwise. This level reduces to zero as R4 is turned fully counterclockwise. The signal from the shunt R3 is applied to the other input of IC301. The output of IC301 is amplified by Q301 and Q302. The DC level at the collector of Q302 is proportional to the phase angle delay of the SCRs. the higher the DC level, the greater the conduction angle. When Q302 is cut off, which occurs before the lamp load is ignited, the voltage at its collector rises to about 10 volts. This excess voltage inhibits action of the SCR firing circuit. R313 controls this effect and is adjusted at low line voltage and maximum output voltage and current so as to have no effect on normal linear operation. Page 8 of 21

IV.3.3 firing circuit and phasing transformer Each SCR trigger pulse is generated and shaped by one of six identical pulse amplifiers and secondary windings of phasing transformer T107. The phase angle delay of all pulses is determined by the control signal from the current regulator. The primaries of T107 are connected to the input power in a predetermined phase relationship. Each secondary of T107 is center-tapped and drives a pair of pulse amplifiers. To simplify the description of circuit operation, only one of six channels will be described. R106 and CR106 square off the sinusoid from T107. R112 and C106 integrate the square wave into a ramp. Normally the positive ramp would only approach 0.6V peak and the base of Q106 would not be driven sufficiently positive to conduct. However, superimposed on this ramp is the control signal from the current amplifier, introduced at the center tap of Q107. This positive voltage, added to the ramp, causes Q106 to conduct sometime during the rise time of the ramp. Conduction is rapid and the sudden change of current through the primary of T106 develops a voltage pulse across the secondary which triggers the gate of CR6. The higher the control signal voltage, the earlier each trigger pulse is produced, hence the greater the conduction angle of the SCRs. IV.3.4 over current kill This circuit protects the lamp load against excessive current caused by failure in the current control channel or an open circuit fault in the local or remote programming circuit. A reference voltage derived from zener diode CR305, and adjusted by R323, is applied to one input of IC302. A voltage proportional to output current is taken from the shunt R3 and applied to the other input of IC302. When the shunt signal exceeds the signal at the gate of Q306 which conducts and grounds the control signal, it disables the firing circuit. IV.3.5 sequence and timing circuit This circuit inhibits operation of the boost regulator and igniter trigger under the following conditions: lamp load current flowing, or CURRENT control set fully CCW, or after a period of unsuccessful lamp ignition attempts. Inhibition occurs via CR202 and CR204 whenever Q305 is in saturation so that the "inhibition" line approaches zero. When the CURRENT control is set fully CCW or lamp load current is flowing, the output of IC301 is positive. The current flowing through R315 causes Q303 to conduct which places Q304 into conduction. This causes current to flow through R319 saturating Q305. When the CURRENT control is turned more than about 15 degrees CCW, and the lamp has not yet been ignited, the output of IC301 is negative. This cuts off Q303, Q304 and Q305 and permits initiation of the starting sequence after a period of 10 to 20 Page 9 of 21

seconds following power supply energization, C303 has charged through R318 to a voltage level sufficient to cause Q305 to saturate thus inhibiting the ignition sequence. When the power supply is turned off, C303 discharges rapidly through CR302 to reset the starting sequence. IV.3.6 boost regulator This circuit regulates the boost voltage at a present level, and gates it on or off in response to the inhibit signal from the sequence and timing circuit. IC201 compares a reference voltage derived from zener diode CR201, at one of its inputs to a sample of the boost voltage taken from the positive side of the filter capacitor and reduced by an adjustable voltage divider consisting of R202, R203 and R204. Whenever the boost voltage falls below the level present by R203, the output of IC201 goes negative thus cutting off Q201, R211 and C202. If the boost voltage exceeds the present level, the output of IC201 goes positive thus saturating Q201 and disabling Q202. The oscillator pulses are amplified by Q203 and produce a train of trigger pulses at the gate of Q204, and CR203 form a gated half wave rectifier from T2 and the phase, a secondary of T1 (except on "transformerless" units). The resultant pulsating DC voltage is applied to the positive side of the filter capacitor through current limiting resistor R1. Whenever the "inhibit" line approaches zero (see Section 4.3.5), CR202 conducts and disables the oscillator thus turning off the boost voltage. IV.3.7 igniter trigger The igniter trigger circuit gates the AC power to the igniter on or off in response to the inhibit signal from the sequence and timing circuit. The operation of this circuit is very similar to that of the boost regulator except that it has no regulating function, and it has a triac switch in place of an SCR. In this circuit, the inhibit signal disables the oscillator via CR204. IV.4 HIGH VOLTAGE IGNITER EMKI units are equipped with a built-in igniter assembly which provides the high-voltage pulse necessary to start the lamp. During the igniter sequence, the 220VAC from Phase A of the input is applied to the primary of T302 through the conducting triac of the igniter trigger circuit. T302 steps this voltage up to 440V and applies it to three series-connected voltage doublers on the A300 printed circuit board. The resultant DC voltage charges C301 through R305 and R306 until discharge tube V301 breaks down allowing C301 to discharge rapidly through the primary of T301. This pulse is stepped up by T301 and superimposed on the operating and boost voltages. On super igniter units (for use with ILC lamps), there are two boost voltages. The primary boost voltage of 700VDC is applied across C3 and C4 by the boost regulator (See Section 4.3.6). The secondary boost voltage of 2.7kVDC comes from the output of the voltage doublers on A300 and is applied across C5 through R312 and R313 on A300. CR7, CR8 and CR9 keep the voltages isolated until lamp ignition occurs, and then permit passage of lamp load current. Page 10 of 21

On "transformerless" units, there is no isolation between the input and output circuits and therefore the negative output and auxiliary terminals must never be earth grounded. On these units, V1 is a safety spark gap which prevents the negative side of the power supply from rising to a dangerously high voltage, in the event of an arc-over or short circuit in the lamp assembly, the igniter or any of the high-voltage connections. Page 11 of 21

V MAINTENANCE Please refer to the warranty at the front of this manual before proceeding with servicing or repair of this unit. CAUTION: 1) To avoid serious damage, all test equipment MUST be isolated from the power line and from earth ground when making measurements on the primary side of all units, or at any point on "transformerless" (no T1) units. Since test equipment cabinets may be "floating" at several hundred volts above ground potential, extreme caution against shock hazard must be observed. 2) On EMKI units, NEVER attempt to measure ignition pulse voltages at the POS (igniter) terminal, or on the HV igniter assembly, without using a suitable high-voltage probe. As a general precaution, remove the jumper between TB3-18 and TB3-19 at all times except when HV igniter pulses into a lamp load are desired. NOTES: 1) Terminal TB3-13 is considered as "ground" for voltage measurements made during servicing. 2) All measurements may be made with a 20,000 Ω/V Multimeter (See CAUTION 2 above). 3) Components referenced may not be applicable to all models. 4) The SCRs and their heatsinks are coated with silicon grease to ensure good thermal contact with the chassis, bottom cover, and center partition, all of which form part of the heat dissipation system. Before reassembling any of these parts, be sure that the mating surfaces are clean and have a thin coating of Dow Corning #5 compound or equivalent. V.1 PARTS REPLACEMENT In general, replacement parts are completely defined by the values and tolerances indicated on the schematics. However, certain values are selected at the factory. If any of these components requires replacement, the value of the component in the unit should be used rather than the nominal value on the schemati Replacement of certain components, such as reference diodes, may necessitate some recalibration of the unit. The following components are accessible by removing the bottom cover: A100, CR1-CR6 (and associated parts), R3, TS1, C2 and R5 (standard units). All other components are accessible by removing the top cover. V.2 TEST AND CALIBRATION PROCEDURE Page 12 of 21

Before applying input power to the unit, disconnect any wires or jumpers from the igniter interlock terminals TB3-18 and TB3-19. Any controls that have been replaced or misadjusted should be set initially as follows: R302, R310 and R313 centered, R203 fully counterclockwise, R323 fully clockwise. To test the unit properly, the input power should be taken from a variable transformer (variac) and the output should be connected to a resistive load capable of simulating a lamp load at full output power. The output waveform should be monitored with an oscilloscope (see CAUTION at the beginning of this section) and an accurate ammeter should be connected in series with the negative side of the load. a) With load connected and nominal line voltage applied, turn CURRENT control R4 approximately 1/4 turn clockwise and turn the POWER switch on. b) Check to see that the output ripple waveform is 360Hz (300Hz for 50Hz output) and that the output current can be varied by turning R4. If the ripple waveform is irregular, see SYMPTOM 6 of the Troubleshooting Table. If R4 does not control the output, see REMEDY 3d. of the Troubleshooting Table. c) Check for +15VDC across C404 and -15VDC across C405. d) With maximum rated line voltage applied, turn R4 fully clockwise and adjust R302 for maximum rated output current as read on the external test ammeter. Adjust R2 to calibrate the panel ammeter. e) Turn R313 counterclockwise until ripple waveform becomes stable again. Repeat this procedure with minimum rated line voltage applied. f) To verify operation of the over current kill circuit, turn R323 counterclockwise until the output turns off. To reset the overcurrent kill circuit, switch off the power momentarily. Turn R323 fully clockwise if maximum rated output current is required. Otherwise, R323 may be set to turn off the unit at some lower current limit. g) Disconnect the load, connect a voltmeter across the output terminals, and turn R4 at least 1/4 turn clockwise from zero. Turn the POWER switch on and adjust R203 to produce the required boost voltage (See Section 1.2). On super igniter units, the primary boost voltage of 700VDC should be read across C3 and C4. NOTE: This adjustment must be made quickly after the power is switched on, since the sequence timer times out in about 20 seconds and the boost voltage then begins to decay. To check adjustment, switch off the power, wait 5 seconds, and switch the power on again. h) To check ripple amplitude (see Section 1.2), connect the load and apply maximum rated line voltage. The ripple pattern can be more closely leveled or Page 13 of 21

balanced by selectively shunting capacitors C101 through C106 with resistors in the range of 1/2 to 10MΩ A100 COMPONENT LOCATION VI TROUBLESHOOTING VI.1 A100 TROUBLESHOOTING PROCEDURE NOTES: 1) Where only one terminal is specified, measurements are made with respect to "ground" (terminal TB3-13). 2) Measurements are made with CURRENT control R4 fully clockwise and with the unit under on load (unless otherwise specified). 3) For a description of the theory of operation of the A100 circuits, refer to Section 4.3. Before proceeding, check for +15VDC across C404 and -15VDC across C405. The voltage across each half of the secondary of T2 should be 20VAC (terminals 7-8 and 8-9). VI.1.1 Current Amplifier Page 14 of 21

Check for the following voltages: CR301 6.2VDC IC301 Pin 20 to +50MVDC as R4 is turned min. to max. IC301 Pin 30 to +50MVDC as output current varies from zero to max. rating. IC301 Pin 6Slightly negative. Q302 collector +6 to 8VDC. VI.1.2 firing circuit Check for pulses across primary and secondary of each pulse transformer T101-T106. Check for triangular waveform across each capacitor C101-C106. VI.1.3 sequence and timing circuit During the ignition sequence (i.e.: R4 not at zero, no output current flowing, and timing circuit not timed out), Q303-Q305 are cut off and the "inhibit" line (Q305 collector) is at +15VDC. If ignition is inhibited during the ignition sequence ("inhibit" line near zero), check for negative voltage at Q303, lack of which may mean a defective IC301. VI.1.4 boost regulation During the ignition sequence, check for the following voltages: CR201 5.6VDC IC201 Pin 6 Near zero, varying in step with boost voltage. Q201 Collector Switching on and off as boost voltage varies. Q203 Collector Pulses approximately 15V peak while Q201 is gated off. Q204 gate to cathode Pulses approximately 15V peak while Q201 is gated off. VI.1.5 ignition trigger During the ignition sequence, check for pulses of approximately 15V peak at Q206 collector, and approximately 1VDC gate signal at Q207 gate to MT2. VI.1.6 over current kill During normal operation below the over current trip point, the voltage at IC302 Pin 6 is negative. Check for 6.2VDC across CR305. Check for shorted C306. Page 15 of 21

VI.2 TROUBLESHOOTING CHART SYMPTOM 1. Unit inoperative 2. Power indicator lamp does not come on. 3. No DC output power. d. e. f. d. e. f. g. Blown fuses. CAUSE No input power, or incorrect line voltage or frequency. Power switch S1 or circuit breaker CB1 defective. Relay K1 defective. Thermoswitch TS1 operates because of overheating Defective or incorrect external wiring. Burned out indicator lamp. No input power. Auxiliary fuse blown. Transformer T1 defective. Transformer T2 defective Lack of reference voltage. Shunt R3 defective. Choke L1 defective. Any diode CR7 through CR9 open. d. e. f. d. e. f. g. Check power source. Check fuse rating on schematic and replace. If fuse flows again, check unit. (see SYMPTOM 4). Replace. Replace. Ambient temperature too high - refer to Section 1.2. Check fan. Check air intake and exhaust openings for obstructions. Check external wiring, especially any remote turn-on circuit. Replace complete POWER switch S1. Check power source. Replace. Check primary and secondary voltages on T1. Check primary and secondary voltages on T1. Check remote programming circuitry or shorting link between TB3-10 and TB3-11. Turn R4 fully clockwise. Check for approximately 50mV from TB3-10 and TB3-11 to ground. If no voltage, check R4. If R4 is ok, refer to Section 6.1 Check for voltages between cathodes of SCRs and negative output terminal. If no voltage, check connections or replace R3. Check for voltages between anodes of SCRs and positive output terminals. If no voltage, check connections or replace L1. Replace. REMEDY Page 16 of 21

4. Main fuses blow or circuit breaker trips repeatedly. 5. Ammeter shows current but there is no output voltage. 6. Excessive ripple. 7. High, uncontrolled current output. 8. Poor regulation of drift. 9. Missing or low boost voltage. d. e. f. g. d. Shorted SCR(s). Transformer T1 shorted. Shorted conductors. Any capacitor C1 through C5 shorted. Defective K1 auxiliary contact. Loss of phase, or transformer T1 defective. Transformer T107 defective. A100 defective. Choke L1 defective. Any capacitor C1 through C4 open. R313 misadjusted. Firing circuits unbalanced. Reference voltage defect. Reference or sensing defect. Transformer T2 defective. R1 open. A100 defective. R203 misadjusted. d. e. f. g. Disconnect each SCR and check with an ohmmeter. Replace any shorted SCR(s). Disconnect T1 secondary leads. If fuses still blow, replace T1. Check for shorts between wiring bus bars and chassis. Replace. Replace. Check fuses or circuit breaker. Check power source. Check for voltage across each secondary of T1. Check primary voltage or T107. check for a reading of at least 20VAC across each half of each secondary. Turn R4 fully clockwise. Check for pulses of at least 0.7 volts at each SCR gate. If any gate pulse is missing, refer to Section 6.1. Allow unit to run under full load and check for over-heating of L1. Disconnect one side of each capacitor and make a resistance check across the capacitor. The ohmmeter should dip to a low value, then slowly rising toward infinity. Refer to Section 5.2e. Refer to Section 5.2h. See REMEDY 3d. Check R4. Check connections between R4 and A100, and between R3 and A100. If these are ok, refer to Section 6.1. Check voltage between T2 terminals 3 and 4, or 3 and 6 (see Schematic). If no voltage, replace T2. Replace Refer to Section 6.1. d. Refer to Section 5.2g. Page 17 of 21

10. No boost voltage. (Super igniter units only). 11. No igniter pulse. (Other than EMKI units). 12. No HV ignition pulse. 13. Igniter pulse or HV igniter pulses continue after lamp ignites or after ignition sequence times out. d. d. No primary boost voltage. No secondary boost voltage. Any diode CR7 through CR9 shorted. C5 open. Auxiliary fuse blown Transformer T2 defective. A100 defective. No igniter pulse. Igniter fuse blown. T301 defective. T302 or A300 defective. Q207 shorted. d. d. See SYMPTOM 9. See CAUSE 12a, b and e. Also, with igniter fuse F301 in place, check for voltage rising to 2.7kVDC across C5 during ignition sequence. If voltage is missing or low, check A300 components. Replace. Replace. Replace. See REMEDY 9 Disconnect igniter and substitute a 7 watt incandescent lamp of suitable voltage rating. When unit is switched on, lamp should light during the ignition sequence (10 to 20 seconds). If it does, check igniter and its wiring and repair or replace. If it does not, check AC voltage between A100 terminals J102-14 and J102-16. When unit is switched on, the voltage should go to zero during the ignition sequence. If it does not, refer to Section 6.1. See SYMPTOM 11. Replace. Check for shorted capacitors of diodes of A300. When unit is switched on, V301 should flash several times during the ignition sequence. If it does and on pulse is produced, replace T301. Remove igniter fuse F301 and check for voltage reading of approximately 440VAC across secondary of T302 during the ignition sequence. If no voltage ok, check A300 components. Replace. Page 18 of 21

14. Output current drops to zero as current control is turned up. R323 misadjusted. A100 defective. Remote program circuit defective. Refer to Section 5.25. Refer to Section 6.1. Check for open circuit in wiring or remote programming resistance. Page 19 of 21

SYM F1 F2 F3 F4 F5 F6 F301 RATING 30A-600V 30A-600V 30A-600V 2A-250V 3A-250V 2A-600V 1/8A-250V EMKI FUSE CHART MFR BUSS KTK BUSS KTK BUSS KTK 3AG 3AG BUSS KTK 3AG E/M PART NO. 58-003-020 58-003-020 58-003-020 58-001-008 58-001-009 58-003-008 58-001-001 LOCATION ON BKT BEHIND REAR FUSE PLATE ON BKT BEHIND REAR FUSE PLATE ON BKT BEHIND REAR FUSE PLATE ON BKT BEHIND REAR FUSE PLATE ON BKT BEHIND REAR FUSE PLATE ON BKT BEHIND REAR FUSE PLATE ON A300 PCB INSIDE P/S Page 20 of 21