Johnson Controls YORK YMC2 Operation And Maintenance Manual

Table 99: Cycling shutdown messages
Message Description
MBC – W24 POSITION
The MBC has measured shaft displacement is greater than 100 micron
from center in the orthogonal radial axis designated W at the opposite-
impeller end radial magnetic bearing during Levitation or Rotation
mode (approximately 2/3 of the air gap space to the touchdown
bearing). The MBC Fault contacts open. The MBC remains in Levitation
mode with the motor shaft levitated until commanded to de-levitate
over serial comms. This shutdown is released when displacement is
less than 100 micron.
MBC – VW13
VIBRATION
The MBC has measured synchronous speed (first harmonic) shaft
vibration at the impeller end radial magnetic bearing is greater than 45
micron peak amplitude in Rotation mode. This condition is monitored
only when the AVR and ABS filter is on, which occurs for speed above
70 Hz. The MBC Fault contacts open. The MBC remains in Levitation
mode with the motor shaft levitated until commanded to de-levitate
over serial comms. This fault is released when vibration is less than 45
micron.
MBC – VW24
VIBRATION
The MBC has measured synchronous speed (first harmonic) shaft
vibration at the opposite-impeller end radial magnetic bearing
is greater than 45 micron peak amplitude in Rotation mode. This
condition is monitored only when the AVR and ABS filter is on, which
occurs for speed above 70 Hz. The MBC Fault contacts open. The
MBC remains in Levitation mode with the motor shaft levitated until
commanded to de-levitate over serial comms. This fault is released
when vibration is less than 60 micron.
MBC – Z12
LOW FREQUENCY
DISPLACEMENT
The MBC has measured shaft displacement is greater than 100 micron
axially from the design running position over a 7 second window
(approximately 1/3 of the air gap space to the touchdown bearing
axially). The MBC Fault contacts open. The MBC remains in Levitation
mode with the motor shaft levitated until commanded to de-levitate
over serial comms. This fault is released when displacement is less than
100 micron.
MBC – Z12 POSITION
The MBC has measured shaft displacement is greater than 100 micron
axially from the design running position (approximately 1/2 of the air
gap space to the touchdown bearing axially). The MBC Fault contacts
open. The MBC remains in Levitation mode with the motor shaft
levitated until commanded to de-levitate over serial comms. This
shutdown is released when displacement is less than 100 micron.
MBC - Z12 VIBRATION
The MBC has measured a vibration in axial position at 1 times the
rotating frequency whose amplitude exceeds 60 micron. This frequency
axially can be the image of the rotor axial run-out.
This fault is available when AVR or ABS are activated. The MBC fault
contacts open. The MBC remains in Levitation mode with the motor
shaft levitated until commanded to de-levitate over serial comms. This
fault is released when this displacement is less than 60 micron.
YMC
2
Mod B with OptiView Control Center
106

Johnson Controls YORK YMC2 Specifications

General

Brand	Johnson Controls
Model	YORK YMC2
Category	Chiller
Language	English