Document Subject: Tamson (digital) manual NESLAB ONLINE TAMSON (digital) Instruction and Operation Manual Bath models TMV40DD, TMV45DD, TMV70DD The (V) indicates the presence of a (V)isibility window. The (40), (45), (70) numbers indicate the fluid capacity of the bath in liters. The (DD) suffix indicates the presence of a Digital Display. The (Z) suffix, if present, indicates the presence of a two-stage (Z) pump, which exhibits a suction effect on the return line. Note: While this manual is for those models specifically listed above, all Tamson baths are made of similar components arranged in different configurations. Thus, this manual will also apply to most Tamson digital baths with little interpretation. P.M.T. Tamson Laboratory Equipment PO Box 208 2700AE Zoetermeer The Netherlands Updated 11 November 1997 by NESLAB Instruments ------------------------------------------------- CONTENTS 1. Unpacking 2. Description 3. Controls 4. Temperature adjustment 5. Boost heater operation 6. High temperature / Low liquid level cutout 7. Use of the bath with external setpoint 8. Offset feature 9. Filling 10. Circulation/Pumping device 11. Cooling 12. Temperature protection (automatic cut-off) 13. Defogging visibility window 14. Troubleshooting ------------------------------------------------- 1. Unpacking Retain all cartons and packing materials until the bath is tested and found in good condition. Transport companies generally will not honour a claim for damages if the respective box(es) is (are) not available for examination. ------------------------------------------------- 2. Description The Tamson TMV-DD models are equipped with a proportional temperature controller, digital LED (Light Emitting Diode) setpoint and readout. Excellent stablility is accomplished with an automatic load reset which compensates the proportioning for changes in the bath's heat load. Temperature control is obtained by cycling the control heater at the desired setpoint. ------------------------------------------------- 3. Controls A. Setpoint/Bath temp - When depressed, the Coarse and Fine controls can be used to set the desired operating temperature. B. Coarse and Fine controls - used to set the desired operating temperature. C. Accessory input display select - When in the disable position, the controller will not accept an accessory input signal. In the enable position, the controller will accept an input from an external source. When the bath is used without an accessory, this switch should remain in the disable position. D. Display - 0.5 inch (1.3 cm) LED display with 0.1C resolution and stability. E. Accessory socket - for use with NESLAB programmers or other external input signals. F. Recorder output - Using the red and black terminals on the controller, a 10.00mv/C signal corresponding to the sensor temperature is available. G. Offset output - Using the black and blue terminals a 10.00mv/C signal corresponding to the differential between the sensor temperature and the setpoint is available. H. Motor fuse/circuit breaker - used to reset to pump/stirrer motor in event of overload. I. Power on/off - When switched on, the pump/stirrer/motor will start and the display on the controller will light. J. Heater lamp - indicates the heater is on. Lamp will flash on and off when the heater cycles at the setpoint. K. Safety cutout - adjustable, will shut unit down due to either excess temperature or low liquid level. Calibrated dial is used to set desired high temperature limit. L. Boost heater - When depressed, boost heater will come on and remain on until setpoint temperature is reached, at which time the boost heater will turn off. Boost heater lamp indicates the boost heater is on. ------------------------------------------------- 4. Temperature adjustment Turn the high temperature cutout dial on the bath to full clockwise and depress the reset button with a pencil eraser or other suitable object. Move main power on/off switch to the ON position. This will start the pump/stirrer motor and the display on the controller will light. Turn the accessory input switch to the disable position if the bath is not being used with a ETP or MTP programmer. To set setpoint temperature, depress and hold the setpoint/bath temp button. Turn the coarse and fine control dials until the desired temperature setpoint is shown on the display. Once the setpoint temperature has been set, release the setpoint/bath temp button. The display will now show the bath temperature. As the bath temperature approaches the setpoint temperature, the heater will cycle to maintain temperature. Once the bath has come to stability, the temperature reading in the setpoint and bath temp positions should be equal. Very small adjustments with the FINE control may be required to get the bath temperature and the setpoint temperature to agree. ------------------------------------------------- 5. Boost heater operation The bath is equipped with a boost heater for faster warm up. To engage the boost heater, depress the boost heater button on the front panel. The boost heater will remain on until the bath reaches the setpoint, at which point it will automatically disengage and the main heater will cycle to maintain temperature. ------------------------------------------------- 6. High temperature / Low liquid level cutout All baths are equipped with a High temperature / Low liquid level cutout. A single temperature sensing probe is used to sense either condition. The sensing probe is attaced to the heater, so that low liquid level will be assumed when the exposed surface of the heater becomes too hot, and turns off the bath. To set the High temperature / Low liquid level cutout, locate the adjustment dial on the rear of the bath control box. Turn the dial fully clockwise and depress the reset button. Start the bath and allow it to stabilize at the desired operating temperature. Turn the dial counter-clockwise until the bath stops. Note the position of the dial where this occurs. Turn the dial clockwise above the point where the bath stopped, and depress the reset button. Turn the dial counter-clockwise to a point just above where the bath stopped. With the device set in this position, the entire bath will be shut down on excess bath temperature or low liquid level. ------------------------------------------------- 7. Use of the bath with external setpoint An input signal of a known voltage into pins 1 and 7 will allow the controller to be adjusted by an external source. An output signal at pins 1 and 9 will allow the user to observe the temperature of the sensor. All pins are located on the accessory socket on the front panel of the controller. An input signal of 0.00 mv corresponds to a setpoint of 0.00C. An input signal of 10.00 mv corresponds to a change in the setpoint of 1.00C. The polarity of the signal will determine whether the setpoint is positive or negative. To begin operation of the system, connect setpoint signal to the accessory receptacle of the controller. The accessory/input switch should be in the enable position. Turn the power on/off switch on. Adjust the output signal of the external source to the proper voltage so the desired setpoint appears in the display window of the controller. Allow the system to stabilize at the setpoint. The system temperature will increase or decrease, depending on the polarity of the signal provided. Note: The bath cannot be driven outside of its operating range. ------------------------------------------------- 8. Offset feature Adjust bath temperature as usual. Move display select switch to the offset position. The display will now indicate the difference between the bath temperature and the temperature setpoint. If the bath temperature is above the setpoint temperature, the reading will be positive. If the bath temperature is below the setpoint temperature, the reading will be negative. This information is also available as an output signal of 10.00 mv/C for use with a chart recorder, using the black and blue terminals on the rear panel of the controller. By connecting a 4.5 digit voltmeter to these terminals, a reading of 0.01C resolution is available. ------------------------------------------------- 9. Filling Fill bath with clean distilled water or other bath fluid up to 0.75 inches (20 mm) below the top plate. At no time should the bath level be allowed to fall below 2.5" (6.35 cm) of the top. When using oils for high temperatures, be certain the bath is completely free of water, and be sure to allow sufficient space for the thermal expansion of the oil. If oil must be used, we suggest you contact the oil manufacturer directly. They can usually make a recommendation once they know your requirements. NESLAB Instruments neither recommends nor accepts any responsibility for silicon oils used in this product. For high temperature stability, high boiling point fluids must be used. Besides not degrading at the working temperature, they must also be sufficiently low viscosity in order not to inhibit adequate agitation of the bath fluid. If the bath fluid has too high a viscosity at room temperature, a thermal protector will turn off the bath motor. Continue heating until the bath fluid reaches a sufficiently lower viscosity. Restart the motor by pressing the protector button on the control panel. ------------------------------------------------- 10. Circulation/Pumping device Bath model TMV-45DD is provided with a circulation pump. The outlet and return lines are sized for 5/16" (8mm) ID (inside diameter) hose connections. When working at high temperatures, metal tubing can be connected directly to the fittings. The outlet line is provided with a small disc to stop external circulation. This disc may be replaced if it is desired to stop external circulation. However, it is simpler to connect a small piece of tubing from the outlet to the return fitting and close off the tubing by use of a pinch cock. If flow regulation is desired, use an adjustable pinch cock. When using the bath with the Z (force/suction) pump, the level control provided must be used. Place the outside vessel so the liquid level in it is higher than the liquid level siphoning action when the pump stops. The pump outlet is connected to the smaller metal tube on the levelling device. The pump suction line is connected to the larger metal tube on the levelling device. The levelling device is then supported with a stand and lowered into the outside vessel. The ends of the metal tubing should just touch the water level in the outside vessel. The Z (force/suction) pump cannot be used with foam-forming liquids such as oils, and is, therefore, generally limited to water and temperatures below 100C. However, by closing the suction side of the pump, oil may be used for circulating at higher temperatures to closed systems. ------------------------------------------------- 11. Cooling All bath models are provided with a cooling coil. Cooling may be achieved by passing small amounts of tap water through the cooling coil. Generally, the cooling water should be at least 5C below the desired bath temperature. The correct cooling water flow is indicated by the switching intervals of the heater lamp. Generally, only a few liters of water per hour are required. The heater controller is then adjusted for maximum accuracy. If considerable work below ambient is required, the model IBC-4 or the PBC-2 Portable Bath Cooler is suggested. These units will enable the bath to be controlled at temperatures down to -30C. Important: Cooling is also essential when working slightly above ambient. In some models, cooling is necessary when controlling as high as 40C. This is due to the heat generated by friction at the pump, and by the efficient insulation of the bath itself. The heat is generated slowly; but because of the insulation, it cannot escape. It must be removed by passing a small quantity of cooling fluid through the cooling coil provided, or by the other method mentioned above. ------------------------------------------------- 12. Temperature protection (automatic cut-off) An automatic cut-off is provided as an accessory. Starting of the bath takes place by means of a pushbutton. If, for some reason, the temperature rises above setpoint, the automatic cut-off will shut down the entire bath. The automatic cut-off can be set at any point, but generally is adjusted to one or two degrees above the working temperature. Once the cut-off is actuated, the bath will remain off until the temperature falls below the setpoint and the ON switch is again depressed. ------------------------------------------------- 13. Defogging visibility window When cooling below the dewpoint in the window baths, moisture may condense between the inner and outer glass windows, hindering vision. To eliminate this, dry air or nitrogen can be slowly or occasionally flowed into this area through the screw holes for the support frames on the case. ------------------------------------------------- 14. Troubleshooting Tamson thermostatic baths and circulators have been carefully designed and constructed from the finest components. Field problems are few and most can be located and corrected without difficulty. The following simple tests should pinpoint the cause of any malfunction. ---------- Motor not running, lights on a. check main voltage and all electrical connections, including switches. b. in bath models with automatic cut-off, check that cut-off contact thermometer is set at a higher temperature than main bath controller. ---------- Motor not running, lights operate, motor turns freely by hand a. motor protection switch deactivated motor. Restart by pushing button on panel. If switch deactivates motor repeatedly, check b, c, and d below. b. loose connections, check wiring on rear of motor cover. c. faulty capacitor, replace motor start capacitor located behind front panel. d. motor overloaded. The motor protector device may trip due to mechanical overload of pump. Check fluid viscosity. Check motor guard housing, straighten if necessary. ---------- Bath too hot: red light does not light, motor runs, temperature climbs above setpoint a. at near ambient temperatures, cooling is required. ---------- Bath too cold: motor runs a. improper fluid. Fluid is vaporizing too readily. b. excessive cooling; reduce external cooling c. heater failure d. triac failure on control board fails to turn heater on ---------- No pumping a. outlet tube blocked. The outlet line is provided with a small disc to stop external circulation. This disc may have been inadvertantly left in place. b. pump line disconnected. The pump outlet pipe is press fitted into the pump housing. The pipe may have become disconnected. This may result in fluid being forced between the pump mounting plate and the bath top. ---------- Instability a. If the cooling fluid is being circulated through the cooling coil of the bath when working at near ambient temperature, fluctuations in fluid temperature or flow will affect bath control stability. b. If pressure changes occur in tap water lines, a simple solution is to install a pressure regulator (5-10 PSI)(35-70 kPa) and needle valve in series with the cooling coil. ------------------------------------------------- Updated 1 Dec 1997 by NESLAB Instruments NESLAB Instruments, Inc. PO Box 1178 Portsmouth NH 03802-1178 (800) 4NESLAB (603) 436-9444 fax (603) 436-8411 web: www.neslabinc.com [end]