BARNSTEAD|THERMOLYNE MIRAK™ 4-Place Stirrers and Stirring Hot Plates OPERATION MANUAL AND PARTS LIST SERIES 846, 847 Model # S73130 S73130-26 S73134 S73135 SP3230 SP73230-26 SP73235 SP73235-60 SP73238 SP73238-60 Voltage 240 220-240 100 120 240 220-240 120 120 208 208 Description 12x12 12x12 12x12 12x12 12x12 12x12 12x12 12x12 12x12 12x12 LT847X2 • 5/28/99 1
Table of Contents Safety Information ..............................................................................................................................................3 Alert Signals..................................................................................................................................................3 Warnings ......................................................................................................................................................
Safety Information Alert Signals Warning Warnings alert you to a possibility of personal injury. Caution Cautions alert you to a possibility of damage to the equipment. Note Notes alert you to pertinent facts and conditions. Hot Surface Hot surfaces alert you to a possibility of personal injury if you come in contact with a surface during use or for a period of time after use. Your Thermolyne MIRAK™ 4-Place stirring hot plate has been designed with function, reliability and safety in mind.
SAFETY INFORMATION Caution Space unit 12 inches away from combustible materials under any conditions. Gross weight of items placed on top of 12”x 12” stirrers and stirring hot plates should not exceed 30 lbs. 4 4. Do not remove or modify grounded power plug. Use only properly grounded outlets to avoid shock hazard. Not rated for use in hazardous atmospheres. 5. Use caution when heating volatile materials; top surface and element can reach the “Flash Point Temperature” of many chemicals.
SAFETY INFORMATION Please note the following WARNINGS: Warning This warning is presented for compliance with California Proposition 65 and other regulatory agencies and only applies to the insulation in this product. This product contains refractory ceramic, refractory ceramic fiber or fiberglass insulation, which can produce respirable dust or fibers during disassembly. Dust or fibers can cause irritation and can aggravate preexisting respiratory diseases.
Introduction Your Thermolyne MIRAK™ 4-place stirrer or stirring hot plate is a general purpose stirring or stirring and heating plate designed for laboratory procedures requiring precise control of temperature and/or stirring speed. Each 4-place MIRAK model includes a digital display for monitoring actual stirring speed, and the stirring hot plate models have dual displays so temperature and stirring speed can be monitored simultaneously.
Unpacking Note A special 20-amp cordset is included on the CSA-approved model of the 12” x 12” 120 volt MIRAK 4-place stirring hot plate (SP73235). This 20-amp cordset can only be plugged into a nonstandard 20-amp, 120 volt wall receptacle. If you do not have the appropriate receptacle, contact a qualified electrician for installation of a 20-amp 120 volt outlet. 1. Remove your MIRAK 4-place stirrer or stirring hot plate from the carton. 2.
Installation 8 1. Set the unit on a flat, stable surface at least 12” away from combustible materials and plug the cordset into a properly grounded electrical outlet of correct voltage and current handling capacity 2. Use your right hand to locate the ON/OFF power switch which is on the side, near the front right corner as you face the unit. 3. Press the black ON/OFF power rocker switch to the ON position.
INSTALLATION Front View Back View 9
Principles of Operation Each MIRAK unit utilizes the latest in microprocessor technology to deliver the most reliable, accurately controlled, ceramic top hot plate, stirrer and stirring hot plate on the market. Your MIRAK 4-place 240 volt and 208 volt stirring hot plate has an electronic closed loop feedback control which will accurately maintain temperature setpoints from 40°C to 540°C. The 120 volt MIRAK 4-place stirring hot plate will maintain temperature setpoints from 40°C 370°C.
PRINCIPLES OF OPERATION individual motors in the MIRAK 4-place stirrers and stirring hot plates which produce maximum stirring torque under normal laboratory load conditions. Each motor is combined with a powerful magnet to provide exceptional magnetic coupling with a stirbar. Each motor is centered beneath each of the four stirring positions indicated by the circles silkscreened on the 12” x 12” top plate. All four motors will operate at the same speed.
Operation Removing the Clear Plastic Cover Your MIRAK unit has a protective plastic cover over the front control panel. This plastic cover is designed to protect the control knobs and the display panel from spills, and should remain in place when the unit is being used. To use the knob(s) while the plastic cover is in place, spin the knob(s) from the bottom where the knob projects below the plastic cover.
OPERATION Setting the Stirring Speed The 12” x 12” top plate will accommodate up to four 1 liter vessels, one at each stirring position. The 4-place MIRAK will also stir two 2 liter flasks simultaneously with up to two 1 liter flasks, one at each of the other two stirring positions. Actual stirring speed may differ between larger vessels and smaller vessels stirred simultaneously, depending on the amount and the viscosity of the solution in each flask.
OPERATION seconds. After five seconds the display will automatically return to indicating actual speed and the SET light will go out. To stop the stirring action without changing your setpoint, press the knob once. To resume stirring at the set speed, press the knob again. If you want to ensure that the unit will not start to stir if the knob is inadvertently pressed, turn the speed control knob until the display indicates the word OFF.
OPERATION immersion probe or a chemical-resistant 7” Teflon immersion probe are available through you distributor, or by contacting Barnstead|Thermolyne at 800-553-0039.) Your MIRAK 4-place stirrer or stirring hot plate will accept any ungrounded Type K thermocouple probe, however, the accuracy of probes other than those we’ve tested and specified may exceed the probe accuracy rating we’ve designated. Note The temperature display will not indicate a temperature less than 40°C.
OPERATION Controlling Top Plate Temperature Your MIRAK 4-place stirring hot plate will control the top plate, and the display will indicate top plate temperature WHENEVER THE PROBE IS NOT PLUGGED IN. When the unit is displaying the top plate temperature the word TOP on the front panel will be illuminated. Note The top plate temperatures will be higher than your solution temperature.
OPERATION To obtain an accurate reading when you are using the probe and stirring your solution, make sure the probe is immersed in the liquid and is not located in air in the center of the stirring vortex. Using the Probe with the Temperature Display for Stirring-only Applications On the stirring hot plate model, the probe can also be utilized to monitor the actual temperature of your solution when you want to stir the solution without heating.
OPERATION desired setpoint. Now plug your probe into the unit, change the setpoint to your desired solution temperature, and place the probe in your solution. Without a Probe Note If you allow the top plate to reach the maximum temperature of 540°C while preheating and then turn the control down to a setpoint less than 200°C, the temperature of the top will drop rapidly to 200°C.
OPERATION temperature, metal vessels and sand baths may be heated safely without the danger of the ceramic top breaking. When heating metal vessels and sand baths however, we recommend that you DO NOT use the probe to control the temperature. Because of the heating and cooling properties of metal and sand, the sample temperatures fluctuate, which will result in unstable top plate temperatures.
Operating Specifications Top Plate Surface Solid Ceramic Heating Specifications Temperature range: 40°C - 540°C Heat-up time to maximum temperature (unloaded top plate) 8 minutes Temperature stability at plate surface (@ 70°C) ± 2.0°C Stability of the solution temperature (400 ml of water in a 1000 ml glass flask): Controlled by the top plate at 70°C setpoint (solution maintained at 30°C) ± 1.0°C Controlled by the immersion probe at 70°C setpoint (solution maintained at 70°C) ± 1.
General Operating Specifications Dimensions - 12” x12” models Model Numbers Overall Width Overall Height Overall Depth Top Plate Width Top Plate Height Top Plate Depth Weight lbs. (kg) SP73235 SP73235-60 SP73230 SP73230-26 SP73238 SP73238-60 S73135 S73130 S73130-26 S73134 13.500 (34.29) 6.750 (17.15) 16.625 (42.23) 12.375 (31.43) 13.500 (34.29) 6.438 (16.35) 16.625 (42.23) 12.375 (31.43) 12.375 (31.43) 25.74 (11.68) 12.375 (31.43) 22.13 (10.04) Electrical Ratings - 12”x 12” Models Model No.
Maintenance and Servicing Warning Disconnect from the power supply prior to maintenance and servicing. Refer servicing to qualified personnel. MIRAK Interior 22 Replacing the Power Board and or the Logic Board 1. Unplug unit, turn unit upside down and remove screws from bottom. 2. Open unit. Locate power board and logic board (see photo). 3.
MAINTENANCE AND SERVICING 5. Note the position and color of wires and cable connected to the power/logic board assembly, paying particular attention to the position of the black wires connecting each of the four stirring motors to the boards. 6. Disconnect wires attached to the power/logic board assembly. If you have a stirrer skip to step 9. 7. On stirring hot plate models note the position of the wires running from the thermocouple for the top plate. Remove these wires from the logic board. 8.
MAINTENANCE AND SERVICING 12. Position the power/logic board assembly in place and secure the four screws which mount the bracket for the board assembly to the metal plate. 13. Reconnect all wires and cables and reassemble the front display panel. 14. If the logic board was replaced, locate the jumper wire at position J3 on the logic board and move this jumper wire to position J5 on the logic board. 15. Proceed to the set-up procedure.
MAINTENANCE AND SERVICING Power Board for stirring hot plate detailing correct placement of wires and cables Power Board for stirrer detailing correct placement of wires and cables 25
MAINTENANCE AND SERVICING Replacing the Motors 26 1. Unplug unit, turn unit upside down and remove screws from bottom. 2. Open unit. Note position and color of wires and cables connected to the logic, power and display boards. 3. Remove the display board as noted in steps 3 through 5 under “Replacing the Display Board.” 4. Remove the logic and power board assembly as noted in steps 5 through 8 under “Replacing the Power and/or Logic Boards.
MAINTENANCE AND SERVICING wires coming from the probe receptacle at the back of the unit and disconnect these wires from the logic board. 11. Remove the 6 screws which secure the metal plate to the case. 12. Pick up the whole metal plate assembly with the power board/logic board assembly still attached. If you have a stirring hot plate model, carefully thread the element wires through the holes in the metal plate. 13. Flip the plate over. 14.
MAINTENANCE AND SERVICING 20. Screw the bracket with the logic board/power board assembly back onto the metal plate. 21. Reattach all wires. 22. Replace display board and attach cables. 23. Bundle wires and resecure with tiestraps. 24. Replace bottom and secure with screws. Replacing the Top Plate Assembly 28 1. Unplug unit, turn unit upside down and remove screws from bottom. 2. Open unit. Note position and color of wires and cables connected to the logic, power and display boards. 3.
MAINTENANCE AND SERVICING 7. Locate the top plate THERMOCOUPLE wires attached to the logic board. Detach these thermocouple wires from the logic board. 8. Remove the THERMOCOUPLE wires coming from the probe receptacle at the back of the unit and disconnect these wires from the logic board. 9. Locate the screws holding the top plate assembly and attach to the case. You can access the screws through the four holes in the metal plate or remove the metal plate and then unscrew the top plate assembly. 10.
MAINTENANCE AND SERVICING Note The set-up procedure should be followed whenever the top plate assembly or the logic board is replaced in your MIRAK 4-place stirring hot plate. The set-up procedure is not necessary when replacing the top plate or the logic board in the stirrers. Logic Printed Circuit Board 30 15. Bundle wires and resecure with a tiestrap. 16. Replace bottom and secure with screws. 17. Proceed to set-up procedure.
MAINTENANCE AND SERVICING Set-Up Procedure 1. Place a 500 ml flask with 300 ml of water on the top plate. Place a standard laboratory thermometer (do not use the probe for this procedure) 1/2” above the bottom of the flask. 2. Turn the unit on and set the temperature at 70°C. Allow the unit to operate at this temperature for five hours. 3. At the end of five hours note the temperature measurement on the thermometer and subtract 44° from the thermometer reading to determine the absolute value.
MAINTENANCE AND SERVICING 6. Locate the black plastic jumper on the logic board at position J3. (See the illustration of the Logic Printed Circuit board.) Remove the jumper and secure it across both pins at position J5. If you cannot locate the jumper, contact Barnstead|Thermolyne. 7. Reattach the logic board bracket on your stirring hot plate model and realign the pickup slot with the encoder wheel (refer to the instructions in this manual for reassembling the logic board with the encoder wheel).
MAINTENANCE AND SERVICING minus 3, turn the knob COUNTERCLOCKWISE, counting each click of the knob until you have advanced the knob the same number of positions as the number you calculated in step 3, and then one additional click. 10. Push the heat knob again. The PROBE, SET and TOP lights will no longer be illuminated. 11. Turn the power switch to the OFF position, unplug the cordset from the power source, and allow the top plate to cool completely. 12.
MAINTENANCE AND SERVICING and remove screws from bottom. 2. Open unit. Locate the logic board. (See illustration of the interior of unit or the exploded view.) Move the jumper position J3 to position J5. For series 732 units, you must remove jumper J4 if it exists. 3. Replace the bottom of the unit and turn the unit over. 4. Calculate the necessary correction for the probe using the following equation: Note The Maximum error is ±10. Thus the correction must be between 340 and 360.
Troubleshooting Problem Solution Unit is not operating at all. Check power. Replace circuit breaker on power switch. Unit is stirring or heating but no lights are lit on the display. Check cable on display board. Only the power light is lit on the display. Check ribbon cable connection from the power board to the logic board. It may be upside down. Replace display board. Some digits of the display are not lit. Replace display board. Display does not increase or decrease when knob is turned.
Exploded Views 4-place Stirring Hot Plate 36
EXPLODED VIEWS 4-place Stirrer 37
Replacement Parts To ensure your safety and for proper operation, the ceramic top plates for hot plates and stir plates are only sold as complete assemblies. This assembly includes the ceramic top, element, thermocouple, insulation, baffle plate and 2 ceramic top holders. Key Number 1 2 3 4.
Ordering Procedures Please refer to the Specification Plate for the complete model number, serial number, and series number when requesting service, replacement parts or in any correspondence concerning this unit. All parts listed herein may be ordered from the Barnstead|Thermolyne dealer from whom you purchased this unit or can be obtained promptly from the factory. When service or replacement parts are needed we ask that you check first with your dealer.
One Year Limited Warranty Barnstead|Thermolyne Corporation warrants that if a product manufactured by Barnstead|Thermolyne and sold by it within the continental United States or Canada proves to be defective in material or construction, it will provide you, without charge, for a period of ninety (90) days, the labor, and a period of one (1) year, the parts, necessary to remedy any such defect.
