For installation instructions refer to the mounting and dimensions details and the terminal layout drawings on page 5 of this manual.

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Arthur Fleming
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1 Provisional Instruction Manual The MSSD33 suspended solids detector is a microprocessor-based instrument to detect the suspended solids/water interface in pipelines. The instrument consists of two components, an S20 sensor that is mounted in the pipeline and a surface mounted microprocessor based electronics module with three relay outputs. The instrument measures the attenuation of light caused by the increase of solids in a liquid. The units of measurement are probe signal units, a number derived from a calculation performed within the unit. If required, these probe signal units (psu s) can be related to physical measurements in g/l, ppm, etc., by comparison with known liquids or laboratory analysis. For installation instructions refer to the mounting and dimensions details and the terminal layout drawings on page 5 of this manual. CONNECTORS All the terminals are of a two-part design which when pulled, split in the middle to allow for easy wiring. RELAY CONNECTIONS The connectors on the left hand side are marked R1, R2 and R3. These are connected to the relays R1, R2 and R3. Relays R1 and R2 are the control relays which are energized when the probe signal exceeds the setpoint, which are rated at 240 volt AC and 10 amps. There are two LED s associated with these relays and LED 1 is illuminated when relay one is energized. LED 2 is illuminated when relay 2 is energized. Relay R3 is a fault relay and should be wired back to a PLC or alarm annunciator panel. The relay is voltage free and has a SPNO contacts rated at 24 Volt AC and 0.5 Amp. This relay will only operate when the internal microprocessor is unable to make sense from the information being received from the sensor. This relay is normally energized. It de-energizes when the probe signal has been above 10,000 probe signal units for a period of 90 seconds or when there is a power failure. SUPPLY CONNECTION The center two-way terminals are for the supply voltage which is a nominal 24 Volt DC. The terminals are marked with the correct polarity, however the unit is reverse polarity protected should the polarity be accidentally reversed. The unit has a current requirement of approximately 150mA on start up and is fused at 200mA. The 24 Volt DC supply has a MOV to prevent electrical spikes from damaging the instrument and it also has a resettable fuse. If for any reason the instrument draws more than 200mA then the fuse will go open circuit. To reset the fuse, remove the 24 Volt supply and the fuse will close again. No damage will come to the fuse and it never needs replacing. Page 1 of 7

2 SENSOR CONNECTION The right hand connector is for the sensor and the colour coding on the label corresponds to the wire colour coding on the sensor. SET POINT ADJUSTMENTS The only user adjustments are the rotary set-point switches that are located at the top left and right of the lower printed circuit board. The switches are representative of probe signal units, (psu s) a dimensionless number that is calculated from the attenuation of the infrared light. The top left switch (RS1) is thousands, the middle switch (RS2) is hundreds and the bottom switch (RS3) represents tens. The right hand switches are (RS4) thousands (RS5) hundreds and (RS6) tens. Typical values of probe signals are 1500 for water and 5000 for whole milk (4 percent fat). The two sets of setpoint switches are not designated as either high or low as you can make either switch a high or a low. The microprocessor looks at both values and directs the information to the appropriate relay. There are a number of software defaults built in for the setpoint adjustments and these are explained below. If either of the setpoints is set less than 1000 psu s, (an impractical value) then the unit defaults that setpoint to a low value of 1000 psu s. If both setpoints are set to less than 1000 psu s then the software will interpret the lowest value as 1000 psu s and the higher value setpoint as 1000 psu s plus the hysteresis value plus 1 probe signal unit. If the setpoints are set closer than the hysteresis value then the lower setpoint will be as indicated on the switch eg 2000 psu s. If the hysteresis is 100 psu s and the higher value is 2080 then the unit will interpret this setting as 2101 psu s. This number is the combination of the lower value, plus the hysteresis (100 psu s) plus 1 probe signal unit. The microprocessor does not read the setpoint and hysteresis values every time it makes a new calculation. If adjustments are made to these settings it will take several seconds for them to take effect. NOTE:-If you require a detection point which is very close to water, then the minimum setpoint value to ensure that the relay de-energizes must be equal to the value of the probe signal in water, plus the hysteresis value plus 100 psu s. For example, probe signal in water is 1500, plus 200 psu s hysteresis (from position of JH1), plus 100 =1800. A probe signal of 1800 would represent a few drops of milk in a 500ml container with a hysteresis of 200 psu s. Page 2 of 7

3 HYSTERESIS (Deadband) The Link JH1 provides hysteresis control at plus and minus 100, 200, 300 & 500 probe signal units. Hysteresis control is used to stop the relay changing state on small changes in probe signal units. There are four sets of jumper pins marked 100, 200,300 and 500 and the shorting link can be moved to any set of jumper pins to give the hysteresis value required for your process conditions. If the link is not connected to any pair of jumper pins then the unit will default to 500 psu s hysteresis. For a pictorial demonstration of the way in which the hysteresis works in practice, refer to the pages 6 and 7 of this manual. PROBE SIGNAL INDICATION There are two multimeter test points marked + (TP1) and (TP2) on the right hand side of the lower printed circuit board. These connections are provided so that you can measure the probe signal units generated by the sensor. The probe signals units calculated from the sensor are in the range 0 to 10,000 psu. The 0 to 10,000 psu s are converted to a 0 to 10 volt DC signal. For example with the sensor in water a 1500 psu reading equates to 1.5 Volts. With the sensor in whole milk a reading of 4900 psu s equates to a reading of 4.9V. Almost any digital multimeter with standard 2mm test connectors and set to the 10 volt DC range can be used to make the reading. TEST CONNECTOR On the right hand side of the lower board is a red connector marked TC1. This is used during manufacture and can also be used with a test box available from Quadbeam Technologies Ltd for on- line diagnostics. SENSOR INSTALLATION. The sensor has a polypropylene body and a 3 inch Triclamp process connection. The sensor is supplied with an EPDM Triclover gasket and a Cherry Burrell (CB) type band clamp instead of a standard two-piece Triclover clamp. The sensor must be installed with the band clamp supplied as it is possible to damage the polypropylene process flange - by over tightening - if a standard Ladish or other manufacturer s clamp is used. Damage to the sensor process flange is not covered by warranty if a clamp other than the CB band clamp is used. CALIBRATION With two setpoints to adjust, it is easier to calibrate the instrument with prepared samples in a container. Suitable containers are opaque plastic beakers which are 80mm (3.0 inches) diameter and about 90 mm (3.5 inches) tall with a volume of about 300ml. Page 3 of 7

4 Glass laboratory beakers are convenient but reflections from the glass may affect the readings. Prepare 500 ml s of sample and fill the beaker with about 200 ml of solution. With the sensor sitting on the top of the beaker, the fingers should be completely immersed in the liquid. If not, top it up, so the liquid covers the fingers. Set-point Adjustment. When the sensor is immersed into the product with the correct value of suspended solids, insert the multimeter probes into the sockets, read the voltage value and adjust the setpoint switches to match. For the second setpoint repeat the procedure with a new liquid for the second switch point. The sensor can now be installed in the line. Suspended solids measurements can be noisy particularly in the transition phase between the product and the water. The MSSD33 uses a number of electronic techniques to reduce the effect of noise to provide a stable reading. The factory setting for the hysteresis jumper is 100 psu s which is often adequate. However, if at the setpoint value, the control relay is changing state frequently and causing plant problems, then adjust the hysteresis to 200 psu s or if it is very noisy to 300 or even 500 psu s. After any adjustments make sure that the cover on the MSSD53 is screwed down. The IP65 rating can only be maintained when the cover is replaced properly. For further information contact New Zealand: David Johnson Quadbeam Technologies Ltd 17 Laureston Avenue, Auckland 1701, New Zealand. Phone**** 64 (9) Or, your local representative. Page 4 of 7

5 *1000 RS 1 JH1 - HYSTERESIS psu psu psu psu JH1 *10 *100 RS 2 RS 3 LED2 (R2//SP2) RS 4 RS 5 *1000 *100 RS 6 *10 R2 (Set point 2) LED1 (R1//SP1) TP1 + R1 (Set point 1) Fault relay SUPPLY SENSOR CONNECTIONS TC1 TP2 R1 (R1//SP1) R2 (R2//SP2) R3 (Fault relay) V DC Rd Br Wh Gr Yl Bl Or Sensor connections Rd - RED Or - ORANGE Bl - BLACK Yl - YELLOW Gr - GREEN Wh - WHITE Br - BROWN - CLEAR (EARTH) Page 5 of 7

6 Hysteresis Drawing 1 A setpoint is equal to the Probe Signal (PS) value at which the relay changes state between energized and de-energized. In order to avoid the relay flickering due to minor fluctuations in PS, a hysteresis band is used. There are two modes of operation, an absolute setpoint mode and a hysteresis mode. For example, with the setpoint level set at 3000 PS and the hysteresis set for +/- 200 PS, there are three points of importance, 3000 PS for the absolute setpoint mode, and for the hysteresis mode these are 2800PS and 3200PS. Initially, the relay is controlled in absolute setpoint mode. When a rising measured PS value crosses 3000 PS, the relay energizes and the operating mode changes to hysteresis mode. In this mode, the relay control software does not care about the measured PS values until it exits the hysteresis band. If the measured PS value rises above 3200 PS, then the control software changes the operating mode to absolute setpoint. If the measured PS value falls below 2800 PS, the relay will be de-energized and the control software will also change the operating mode to absolute setpoint. Page 6 of 7

7 Hysteresis Drawing 2 Similarly with a falling measured PS value, the relay is controlled in absolute setpoint mode. When the measured PS value crosses 3000 PS, the relay de-energizes and the operating mode changes to hysteresis mode. In this mode, the relay control software does not care about the measured PS values until it exits the hysteresis band. If the measured PS value falls below 2800 PS, then the control software changes the operating mode to absolute setpoint. If the PS value rises above 3200 PS, the relay will be energized and the control software will also change the operating mode to absolute setpoint. Fault Relay Connections This relay is energized whenever there is power supplied to the unit and is de-energized when the unit detects a fault condition i.e. where the probe signal exceeds 10,000 PS units. This relay has one pair of single pole normally open contacts and the contacts are normally closed when power is applied to the instrument. Page 7 of 7

Technical Description

Technical Description LUL, 73 Stock Refurbishment Heating, Ventilating & Air-conditioning Multi-stage Thermostat for Saloon 0.1 19-May-02 ISSUED FOR DISCUSSION FK DC Rev. Date Description By Check Copyright