Johnson Controls YORK YVAM 0350, Operation & Maintenance Manual

Page: 101 / 162

Table 91: Cycling shutdown messages
Message Description
VSD SHUTDOWN – REQUESTING
FAULT DATA
The drive has shut down the chiller and the control center has not yet received the
cause of the fault from the variable speed drive from the serial communications link.
The variable speed drive shuts down the chiller by opening the Motor Controller VSD
Stop Contacts. The control center then sends a request for the cause of the fault to the
drive over the serial link. Since serial communications are initiated every 2 seconds, this
message is generally displayed for a few seconds and then replaced with one of the other
drive fault messages.
VSD – SINGLE PHASE INPUT
POWER
The drive monitors the input voltage of all three phases.
Input voltage range
Input voltage single
phase shutdown value
380/415 264 Volts
460 295 Volts
If the input voltage of any one phase drops below the threshold value for the given input
voltage range in the previous table, then this shutdown occurs.
VSD – STOP (FAULT)
CONTACTS OPEN
See the previous message, VSD SHUTDOWN – REQUESTING FAULT DATA . If the control
center does not receive the cause of the Fault over the Serial Link within 20 seconds, it is
assumed it is not forthcoming and that message is replaced with VSD – STOP CONTACTS
OPEN message.
Safety shutdown messages
The chiller can be started after manual resets are performed as detailed in the following table.
Service and troubleshooting information is contained in the YORK YVAM Service Manual (Form 160.88-
M2) and Chiller Service (Form 160.88-M1).
Table 92: Safety shutdown messages
Message Description
AUXILIARY SAFETY
– CONTACTS CLOSED
The Auxiliary Safety shutdown input, connected to I/O Board TB4-31, detects 115 VAC, initiating a
safety shutdown. This input is a general-purpose, user-defined safety shutdown input. The chiller can
be started after the contacts open and the Clear Fault button is pressed.
CONDENSER – HIGH
PRESSURE
The condenser pressure, as detected by the Condenser Transducer, has increased to greater than 200
psig for shells with 235 psig DWP and 295 psig for shells with 350 psig DWP. The control determines
the shell DWP by the condenser model number on the Sales Order Screen. The chiller can be started
after the pressure decreases to less than 140 psig for shells with 235 psig DWP and 235 psig for shells
with 350 psig DWP and the Clear Fault button is pressed.
CONDENSER – HIGH
PRESSURE CONTACTS
OPEN
The contacts of the electromechanical high pressure safety device, located on the condenser shell,
have opened because this device has detected a pressure greater than 204±7 psig for shells with 235
psig DWP and 308±7 psig for shells with 350 psig DWP. The contacts automatically close when the
condenser pressure decreases to less than 160±10 psig for the 235 DWP shells and 230±10 psig for
the 350 DWP shells. The chiller can be started after the contacts close and the Clear Fault button is
pressed.
CONDENSER –
HIGH PRESSURE –
STOPPED
The condenser pressure exceeded 170 psig for shells with 235 psig DWP and 264 psig for shells with
350 psig DWP while the chiller was stopped. The control determines the shell DWP by the condenser
model number on the Sales Order Screen. High temperature condenser water flowing through the
condenser while the chiller is shut down can cause a condenser high pressure condition, resulting
in loss of refrigerant. This safety fault anticipates this problem by annunciating the condenser high
pressure condition. The chiller can be restarted after a service technician performs a special reset
preset procedure.
CONDENSER
– PRESSURE
TRANSDUCER OUT OF
RANGE
The Condenser Pressure Transducer is indicating a pressure that is less than 6.8 psig or greater than
300.0 psig. This is outside the normal operating range of the transducer. This is generally indicates
a defective transducer. The chiller can be started after the transducer is indicating a pressure that is
within range and the Clear Fault button is pressed.
CONTROL PANEL -
INVALID BRAM
On bootup, the panel determines if a 512K BRAM module is installed by a sequence of tests where
data is written and read from address above and below 128K. If the BRAM is not 512K, this shutdown
is generated.
101 YVAM Control Center