Johnson Controls YORK YMC2 - Page 135

Table 92: Safety shutdown messages
Message Description
VSD – DC BUS
LOCKOUT –
DO NOT CYCLE
POWER
When the unit is stopped in a mode where no command exists to energize the
DC Bus, the DC Bus voltage is monitored and checked against a threshold level
of 100 VDC every five minutes. If the DC Bus voltage is higher than the threshold
value, this shutdown is generated. When the condition clears and VSD input
modules tested and determined acceptable the chiller can be started after the
CLEAR FAULTS key is pressed.
VSD – DC
BUS PRE-
REGULATION
LOCKOUT
If the unit fails to complete pre-regulation (due to VSD – DC BUS PRE-
REGULATION fault), it shall have to repeat pre-charge in order to attempt
another pre-regulation. The VSD shall wait 10 seconds before clearing the DC
Bus voltage pre-regulation fault and allowing another pre-charge to start.
The unit’s fan(s) and water pump(s) shall remain energized during this wait
time. The VSD shall allow up to three consecutive pre-regulation related faults
(i.e. VSD-DC BUS REGULATION) to occur. After the third consecutive fault, this
shutdown is generated. When the condition clears, the chiller can be started
after the CLEAR FAULTS key is pressed.
VSD – GROUND
FAULT
This message is generated when the sum of the 3 phases of instantaneous input
current values are greater than the shutdown value for a period of 1 second for
the given model of drive listed below. When the condition clears, the chiller can
be started after the CLEAR FAULTS key is pressed.
Drive model Ground current shutdown value
0490, 0490A 40 Amps
0612A, 0730A 80 Amps
0774 120 Amps
1278A 200 Amps
VSD – HIGH
PHASE A INPUT
BASEPLATE
TEMPERATURE
This shutdown occurred because the Input Baseplate Temperature exceeded
the shutdown value for the given model of drive listed below. After the unit
trips, the VSD fan(s) and water pump(s) shall remain energized until the
temperatures of all three rectifier’s phases drop below the fault-reset threshold
of 165°F (73.8°C). In April of 2016 the shutdown control for the fan(s) and
pump(s) was changed. The control will now keep the fan(s) and pump(s)
running for 2 minutes after the fault occurred. This change occurred in software
version C.HYP.03.04.01, and C.HYP.04.04.01. When this happens, the unit’s fan(s)
and water pumps shall be de-energized. When the condition clears, the chiller
can be started after the CLEAR FAULTS key is pressed.
Drive model High phase a input baseplate temperature shutdown value
0490, 0490A
0612A and 0730A
190°F (87.8°C)
0774, 1278A (380-414 VAC) 170°F (76.6°C)
1278A (460 VAC) 150°F (65.5°C)
VSD – HIGH
PHASE B INPUT
BASEPLATE
TEMPERATURE
See VSD – HIGH PHASE A INPUT BASEPLATE TEMPERATURE message
preceding.
VSD – HIGH
PHASE C INPUT
BASEPLATE
TEMPERATURE
See VSD – HIGH PHASE A INPUT BASEPLATE TEMPERATURE message
preceding.
135
YMC
2
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™
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