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If there is no transition trip, the protective device relay declares a successful transition to RUN cycle and the
corresponding transition flag(s) (current or time, or both, depending on the settings and motor current) is set. The
transition flag(s) is the part of the global output list, which can be assigned to any module input or relay output. If it is
assigned to a relay output, it can control a reduced-voltage starter, switching to full running voltage.
Even if the transition control output contact is not used, the transition function can provide clear indications of the actual
state of the motor (START versus RUN) on the front panel display and via data communications. A good way to do this
is to use the settings of TRN Criteria = TRN T or I and TRNC = 130% of FLA. Modify the latter, if needed, to lie at a
transition value between the starting current and post-start maximum load current. Set the transition timer well beyond
the normal start time to avoid a transition trip.
Start Delays
When the protective device declares a START, all start timers of the enabled functions begin to time. Each of these
timers blocks the respective function until the set delay expires. These start timers are affected by transitions - they run
for the set time, which may be less than or greater than the time of transition. These start delay timers include:
IOC (Instantaneous overcurrent start delay);
•
GOC (Ground fault start delay);
•
UnderLoad (Underload trip and alarm start delay);
•
IUnbalance (Current unbalance trip and alarm start delay);
•
JAM (Jam trip and alarm start delay); and
•
Generic1 to Generic5 (Generic start delay).
•
Note that the generic start delays are not tied to anything, and they can be used to block anything at the User's choice.
Eaton E-Series Motor Relays that have the ability to measure Voltage also have the following additional start delay
timers:
VUnbalance (Voltage Unbalance start delay) - **
•
UnderVoltage -**
•
OverVoltage -**
•
Power
•
Power Factor
•
Frequency - **
•
** - If the time delay for these timers is set to zero, these timers will not wait for the protective device to declare a
START. The protective function will be active immediately.
EMR-4000
www.eaton.com
IM02602009E
459
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