Sterlco Micro Series Water Temperature Control Unit - Manual (Page 24)

Page 24 MICRO Series Water Temperature Control Units
Heaters
The specially designed 3, 6, or 9 kW three-phase low watt density electrical
immersion heaters heat the water, and the controller regulates the temperature.
The standard heater has an incolloy sheath for best heat transfer and low fouling
properties.
Solenoid Valves
MICRO Series systems use rugged, industrial design solenoids with replaceable
coils and/or internal components. The unit is equipped with a ¼” direct acting
solenoid valve.
Pump Starter
MICRO Series high quality IEC-rated Motor Circuit Protectors (MCPs) are
industrial grade motor controls with overload protection and manual reset.
Transformer
High quality industrial design transformers are specified to suit incoming voltage
on the application and provide 115 VAC control voltage. The 115 VAC circuit is
protected by primary fusing and secondary grounding.
Heater Contactor
Your MICRO Series unit uses high-quality IEC-rated industrial grade
electromechanical contactors for heater controls.
Cooling
The controller automatically regulates cooling by opening and closing the
solenoid valve or modulating valve. For direct injection, the unit cools by
removing the required amount of warm water from the system. This process
permits an equal amount of cool plant water to enter the system well ahead of the
pump, allowing it to blend with the system water. The water supply temperature
governs the minimum operating temperature of the unit.
For closed circuit operation, the unit cools by automatically releasing cooling
water through the tubes of the specially designed tube bundle heat exchanger in
each zone. The process fluid, such as water, glycol, or other similar fluid, is
circulated through the shell of the heat exchanger.
Note: The plant water supply temperature governs the minimum
operating temperature of the unit.
Electricals
The pump motor and the immersion heater operate on three-phase 50/60 cycle
nominal voltages with the control circuit operating at 115V single phase. The
control circuit voltage is provided by a single phase machine tool transformer
with a grounded secondary.