Emerson CoreSense Technical Information page 16

Technical Information
Flash
Alarm conditions
code
Warning: Appears when the signal
4
from current
Connection lost
communicated to the sensor module.
CT to sensor
Warning: Appears when there is no
5
communication
Communication
module and sensor module or rack
Error
controller
Trip: Appears when the excessive
current is present in the compressor.
Refer AE bulletin for more details.
6
Locked rotor Lockout: Appears
consecutive locked rotor trip alarms
occur.
Trip: Appears when there is a missing
phase / single phasing.
7
Lockout: Appears
Missing phase
consecutive missing
alarms occur.
Possible failure reasons
The current
connected to the sensor module.
sensor is not
Faulty current sensor.
Faulty sensor module.
Communication
™
CoreSense control module and
rack controller has been lost.
between control
Communication
™
CoreSense control module and
the sensor module has been lost.
Motor rotor is mechanically seized.
Excessive current present in the
compressor.
when 10
Damaged valve plates in cylinder
head.
Loose wiring connections at the
terminals inside compressor T-Box.
when 10
Worn out contactors.
phase trip
Line break in one of the phases.
Troubleshooting measures
Verify if the CT connector is connected to the sensor module. If not connect the 4-pin
current sensor connector into the sensor module.
Verify if there is continuity between pin 3 & 4 (closest to the latch) of the current
sensing connector. The resistance should be less than 1 Ω. If the resistance is
sensor is not
greater than 1 Ω, replace the current sensing module. Be certain that the receptacles
are fully engaged in the connector block.
Verify if the Amp and Volts values are correctly displayed. If not, inspect the wire
harness connector to ensure that the pins are fully engaged.
If the above-mentioned trouble shooting measures didn't give the positive results, the
reason is faulty sensor module or mis-installed connector. Replace the faulty sensor
module with new one.
Is there a communication network? If not, set the network dip-switch to "stand-alone"
and press reset.
between
Is there a communication network? If not, verify that the communication harness is
engaged at both the CoreSense
If the LED on the top edge of the sensor module is dark, verify 24VAC power to the
between the sensor module, or replace the sensor module.
If communication network amber light is continuously on, reverse the communication
wire polarity. If voltage between centre pin and the right or left pin isn't 2.3-2.6VDC,
inspect for communication wire failure or wire strands that are "shorting" between the
wires or to ground.
Verify that motor voltage is adequate (+/- 10% of nominal rated voltage), especially
during the starting event.
Start compressor with no load. If it does start with no load, inspect the valve plate(s)
for damage or look for other causes of leak-back.
Verify voltage supply from the main power buss.
Verify voltage into and out of contactor (Repair or replace contactor if necessary).
Verify that motor electrical connections are tight at the compressor motor terminals.
D7.21.2/1011/E
™
module and the sensor module.
16/17