4.1.1 Fault, Trip and Limit indicators
Identified by
--
in Figure 3.
Fault indicator:
This indicator is red in color and is lit if the unit gets any faults. No
power is being delivered to the load and the heat OFF indicator will be lit.
There are six fault statuses displayed on LCD:
E-STOP: Indicates that the unit is in Emergency stop status.
AUX INT: An auxiliary interlock wired to the unit has tripped it.
DOOR OPEN: Indicates that the door of the unit is not closed.
WATER PRESS: Indicates that there is inadequate differential water pressure.
WATER TEMP: Indicates that the temperature of the inlet water has exceeded the
allowable level. (see 5.2.)
PARAMETER: Indicates that the wrong parameters have been set. (see 5.2.)
Trip indicator:
This indicator is red in color and is lit when the unit has been tripped. No
power is being delivered to the load and the heat OFF indicator will be lit.
There are three trip statuses displayed on LCD:
SW/THRU TRIP: The inverter circuit failed or swing through signal missing due to a
short in the load, heat station component or poor tuning of the heat station
components.
RES TRIP: The circuit momentarily operated below the resonant frequency due to
e.g. a short in the load or heat station component or poor tuning of the heat station
components.
I.C TRIP: The inverter current momentarily exceeded the set maximum peak value
due to e.g. a short in the load or heat station component of poor tuning of the heat
station components.
Limit indicator:
This indicator is yellow in color and is lit when the heat station is not
properly tuned. The power output of the unit is limited below the desired level set by the
power knob or remote input. There are four limit indicators:
POWER LIMIT: If lit the power is being limited at 12.5kW.
FRQ LIMIT: If lit the circuit is being limited at the resonant frequency of the
resonant tank.
C.V LIMIT: If lit the capacitor voltage is being limited at 500V or 700V rms.
I.C LIMIT: If lit the inverter current is being limited at 250A peak. (Note: The load
coil current could be much higher than 250A peak).
C.V, I.C and FRQ limit can occur simultaneously and those limit messages can be
displayed together e.g. if C.V limit and FRQ limit occur at once “FRQ/C.V LIMIT” will
display.
If any limit indicators are lit, the heat station components needs to be adjusted to obtain
the required power (see section 6.2).
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