POWER SUPPLY UNIT FOR 3 KW MAGNETRON TECHNICAL NOTE

Transcription

1 POWER SUPPLY UNIT FOR 3 KW MAGNETRON TECHNICAL NOTE (Issue April 2004)

2 CE Declaration of Conformity Dichiarazione di Conformità CE Manufacturer s Name: Nome del Costruttore: Manufacturer s Address: Indirizzo del Costruttore: ALTER s.r.l Via Curie, Reggio Emilia - Italy Declare that the microwave generator: Dichiara che il Prodotto: product name: nome del prodotto model: modello Complies with the following norms: Soddisfa le seguenti norme: FX950 FX950 FX950T FX950T EN : A2: 1996 (EN 61010: A2: 1995) EN55011: 1991 The products listed above comply with the requirements of the Low Voltage Directive 73/23/EEC. I Prodotti sopraindicati sono conformi con la Direttiva di Bassa Tensione 73/23/EEC Reggio Emilia, Aprile Marco Garuti Presidente C.d.A. Rev. Note di revisione Data File 0 Prima emissione Aprile 2004 FX950T_r0eng File: FX950T_r0eng - April Technical note: FX 950 T page 1 of 8

3 General Description FX950T is a stabilized ferro-resonant power supply unit, with a fixed output, for a 3kW powered magnetron. The power supply unit must be connected to the 2 x 400V/50Hz electric network without neutral, and is provided in open frame version to be assembled in the electrical panel. General Information The FX 950 T power supply unit is in compliance with the EN (=CEI 66-5) European Standard approved by Cenelec on 9/3/1993. As provided by this standard, the equipment must be installed and used exclusively by qualified personnel instructed on the precautions and operating mode. The generator, if correctly installed, is in compliance with the expected radio noise limits for Group 2, Class A equipment provided by the EN regulation. CAUTION! FX 950 T is powered through the mains: read this manual carefully before installing the equipment. Make sure that the electric connection and the utilisation are correct. Failure to comply with the instructions implies serious risks for the personnel in charge of the equipment utilisation, as well as the possibility to cause equipment breakdowns. Electric Specifications Power supply (rated): 400Vac, 50Hz Minimum input voltage: 360V Maximum input voltage: 440V Input current (average value): V Rating: 4400 VA Efficiency: 95% Magnetron power: 3 kw Outgoing stability: +/-7% Outgoing anodic current: 840 ma Magnetron: 2M265-M12 Environmental working conditions Operating mode: only inside the panel Altitude: tested up to 2,000 m above sea level Temperature: from 5 C to 40 C Relative humidity: 80% up to 31 C, linear decrease by 50% at 40 C Level of pollution: 2, in compliance with IEC664 Fuse specifications FX 950 T has two (F1 and F2) fuses assembled on the control card and one (F3) fuse assembled on the autotransformer. F1 fuse data: - Size, type: 5 x 20 mm - Operating speed: delayed (T) - Rated current: 2 A - Rated voltage: 250 V F2 fuse data: - Size, type: 5 x 20 mm - Operating speed: delayed (T) - Rated current: 100 ma - Rated voltage: 250 V F3 fuse data: - Size, type: 5 x 20 mm - Operating speed: delayed (T) - Rated current: 1 A - Rated voltage: 250 V page 2 of 8 File: FX950T_r0eng - April Technical note: FX 950 T

4 Component layout V input 9 10 Connection of the high-voltage cable to the magnetron Earth screw List of components Pos. Q.ty Description Code Notes 1 2 High-voltage capacitor CR132A3K0 2 1 H.V. transformer 42AN x20 2A T 250V fuse F1 4 2 H.V. Diode 80D Measure resistance RSZ25002R V -230V autotransformer 42ATC140/ x ma T 250V fuse F x20 1A T 250V fuse F3 9 1 Control card Data label File: FX950T_r0eng - April Technical note: FX 950 T page 3 of 8

5 Fuse replacement Replace the fuses as follows: -turn the voltage of the power supply unit off; -remove the cap of the fuse holder; -replace the fuse with a new one with the same electric characteristics; -check the fuse holder and in case of oxidation or burns, replace it; -reassemble the cap of the fuse holder; -turn the voltage of the power supply unit on; Refer to Fuse specifications for the value of the fuses. Connection instructions I) The power supply unit must necessarily be earthed by means of the input earth clamp (central clamp looking from the clamp side) with a 2.5mm ² cable; II) The microwave head must be connected to the power supply unit by means of the earth wire (yellow-green) provided on either the head and the power supply; for safety reasons, another earth wire must be placed on the earth terminal on the head. III) The connections between the head and the power supply unit are carried out by means of plugs and terminals: do not turn the power supply on if all the cables are not correctly connected and fixed in their positions. IV) Apart from the connection cables to the head, the connections to RACK POWER UP, ENABLING signals and to the INTERLOCK chain are required (closed contact to supply power). If INTERLOCK is not to be used, terminals 6 and 7 can be connected together on connector J5. V) Install an external switch in order to disconnect the main power supply, to be used each time maintenance operations must be carried out on the power supply unit. VI) The characteristics of the external switch must comply with the EN standard, it must be installed near the power supply unit and easily reachable by the user. VII) In order to carry out the connection to the terminal board of J2 mains input, make sure that the mains is not connected through a the external switch. Failure to comply with these instructions is dangerous for those who use the equipment, apart from the possibility to cause equipment breakdowns. Power-up procedure Complete the connection correctly before setting at work. Caution: if the power supply unit is powered without the provided high-voltage connection between the power supply unit and the magnetron, on the outgoing Faston connector there is a dangerous voltage; DO NOT restore the high-voltage connection before discharging the capacitor to earth by means of a suitable insulated tool. Caution: connect with a direct cable the earth screw of the head with the earth screw of the power supply unit. Failure to make this connection may cause danger of death! Activate the external switch to power the equipment; FX950T is completely powered by activating the RACK POWER UP input with a 24Vdc voltage. The presence of the mains is indicated by the green pilot light POWON on the M330 card. Wait at least 20 seconds for the preheating of the magnetron filament before providing the enabling signal. Activate the output power to the microwave head by activating the ENABLING input. The output of the unit is interrupted when: 1) the ENABLING signal stops 2) the INTERLOCK chain (temporary or permanent opening of the NC interlock circuit) is opened 3) the safety thermostat (T=130 C) placed in the highvoltage transformer TR2 is opened. 4) the safety thermostat (T=100 C) placed on the Magnetron is opened. 5) one of the fuses blows. 6) the RACK POWER UP signal stops page 4 of 8 File: FX950T_r0eng - April Technical note: FX 950 T

6 There are also two other safety mechanisms: a) the first one stops the output if the anodic current drops below the minimum current threshold (ca 40% of the rated current). For example, this may depend on the opening of the high-voltage circuit. b) The second one stops the output if the anodic current exceeds the over-current threshold. For example, this may occur in case of short-circuit to earth of the highvoltage connection, or in case of current leakage due to humidity or dirt along the high-voltage path. After activating ENABLING, if no interlocked conditions are present, the ABIL.MW led is lit on M330. Within 5 seconds, the filament voltage limitation relay is switched: the RIDUZ. FILAM. led is fully lit and the filament voltage drops to an appropriate value. ALARM CONTACT The alarm contact is closed when the rack is turned off and when all is working properly, but opens in case of alarm. The contact remains open also after the end of the alarm, until the ENABLING signal is removed. Any alarm immediately disables the microwave ENABLING relay. The coils of the RACK POWER UP and MW ENABLING relays require 24Vdc 2.2 VA. NOTES: 1) When ENABLING is activated, no power is supplied if any of the breakdowns mentioned above occurs. 2) In case of alarm, in order to restart the issuing of microwaves it is necessary to 1) eliminate the cause of the alarm and 2) remove the ENABLING signal for at least 2 seconds, and then restart it. 3) Each time the rack is completely turned off, (for ex. disabling of the RACK POWER UP signal, or opening of the INTERLOCK chain) wait 20 seconds after turning the rack on, before starting the ENABLING. 4) After this delay, the ENABLING signal can be activated and deactivated without waiting, for 5 second minimum both for ON and OFF. 5) Always open the external switch before replacing the fuse or making connections to the power supply unit. File: FX950T_r0eng - April Technical note: FX 950 T page 5 of 8

7 Wiring diagram of FX950T power supply unit with TX030 head Caution: it is compulsory to connect the earth screw of the head to the earth screw of the power supply unit: failure to do this may cause a death risk page 6 of 8 File: FX950T_r0eng - April Technical note: FX 950 T

8 EXTERNAL WIRING DIAGRAM File: FX950T_r0eng - April Technical note: FX 950 T page 7 of 8

9 Physical characteristics - width: 250 mm - height: 235 mm - depth: 676 mm - weight: 40 kg View of the power supply unit How to order Power supply unit for filament :FX 950 T Alter reserves the right to make improvements or changes to the product described in the manual at any moment and without prior notice. This publication cannot be reproduced without the written consent of Alter. Technical assistance: Alter s.r.l Reggio Emilia - ITALY Tel: ; fax Web: All rights are reserved. page 8 of 8 File: FX950T_r0eng - April Technical note: FX 950 T