Sterlco Micro Series Water Temperature Control Unit - Manual (Page 33)

MICRO Series Water Temperature Control Units Page 33
bars, 68.95 kPa/0.69 bars differential]) opens. You need at least 16 psig
(110.32 kPa/1.10 bars) for the best cooling capacity and to prevent water
boiling in the process circuit at high temperatures, particularly at the pump
suction.
; After venting, the microprocessor controller monitors the TO PROCESS
RTD probe, cycling open the cooling/vent valve to discharge warm water or
energizing the immersion heater to maintain the process set temperature.
5-5 Checking Motor Rotation Direction
Check for correct pump rotation direction by looking at the end of the motor.
Press the ON/OFF switch from the OFF ( O ) position to the ON ( | ) button, and
note the direction that the motor turns. Rotation should be clockwise when
viewed from the motor end.
Note: Make sure that a qualified electrician performs the following
steps.
To change rotation direction:
1. Disconnect and lock out power at the customer supplied fused disconnect.
2. Reverse any two incoming leads at the power terminal blocks.
3. Do not switch leads at the motor or motor starters.
5-6 Shutting Down the Temperature Control Unit
Cool the unit down by selecting a set point of zero ( 0 ). Let the unit stabilize at
one temperature close to the incoming water temperature, then press the
ON/OFF switch to the OFF ( O ) position. Now press the VENT button to
relieve any remaining pressure in the system. Finally, shut off the main power
supply to the unit.
Make sure you provide a correctly sized and protected supply of electrical
power to the unit.
Important!
Refer to National Electric Code (NEC) Article 430-24 through 430-26
for proper feeder conductor and supply disconnect sizing.
Maintain a safe ground and disconnect the power supply before servicing the
unit. A qualified electrician should make electrical connections, and
disconnect and lock out electricity using OSHA 29CFR 1910.147 standards
when you need a service call.