Trebor Quantum Series Di Water Heater - Manual (Page 8)

PAGE 8 QUANTUM DI HEATER OPERATION / MAINTENANCE MANUAL
Figure 2-1
On power up or after the EMO has been pushed, the heater must be
reset by pressing the blue RESET button to reactivate the controls. This
must be done at the machine.
2.4 PROCESS INTERLOCKS
The process fault interlocks are latched into the logic controller (PLC)
memory. When a fault occurs, the user interface will display the alarm
condition and the horn will sound. Pressing the RESET button will
silence the audible horn. The system will retain the fault until it is cleared.
Pressing the RESET button may restart the heater. If the indicator L
ED’s
remain illuminated then one or more faults are still active. Refer to
Section 8, Troubleshooting.
CAUTION: The interlock circuit does not remove hazardous
voltage from the circuit breakers, contactor, and the control transformer.
Only authorized, qualified, trained personnel should service this
equipment.
2.4.a Low Pressure Switch Interlock
The pressure switch will disengage power if system inlet water pressure
drops below 15 psig (103 kPa). The heater will come back online if the
pressure recovers within a 30 second time period. This prevents
nuisance trips due to transient conditions in the DI water supply while still
protecting the heater. However, erratic process temperature control may
result if heater power is disengaged during the pressure transient.