Eaton Cutler-Hammer TRU-START, Operation And Installation Manual

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3.5 FAULTS
When a fault exists the DC Injection DCI relay is de-energized, preventing a properly
interlocked starter from being activated. When an TRU-START DC Injection is used in
conjunction with a C-H starter, this interlock is also carried out through signals passed by
energized the ribbon cable at OPT. When no faults exist and DC injection is not active, the DCI
relay is energize. Therefore, if the 115 VAC supply is not present the "fail-safe" interlock will
prevent the use of the starter. The faults are explained below.
3.5.1 PHASE LOSS
If the single phase power ( 200-600V ) to L1 and L2 terminals is not present, NE1 will
be off and the DCI relay de-energized. When this condition is corrected the unit will
allow the starter to be energized.
3.5.2 INSTANTANEOUS OVER CURRENT (IOC)
If the current feedback exceeds 1000% of the current setup by the burden resistor (Rb),
the unit will trip on IOC and de-energize the DCI relay. LD2 will be illuminated to
indicate an IOC fault and is reset via SW1, RESET. Causes of this fault may be a
shorted output or simply a burden resistor sized too small. Refer to Section 4.4 for
burden table.
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