268
FORM 160.54-M1
ISSUE DATE: 10/25/2019
SECTION 32 - MOTOR MONITORING
JCI COMPANY CONFIDENTIAL
JOHNSON CONTROLS
FIGURE 105 -
MOTOR COOLING COIL LEAK DETECTOR – OPTICAL SENSOR
TB7
5
6
4
GND
+5VDC
CLOSE = OK
OPEN = TRIP
IN
GND
+5VDC
PULL UP SELECT
FROM PROCESSOR
LD15003
Digital inputs (CONTINUED)
• OPITICAL - Enables the optical sensor Digital
Input and displays the leak status, as reported by
the optical leak sensor, via the Motor Monitoring
Board serial communications. The microboard
commands the Motor Monitoring Board to read
the sensor input at TB7-4,5,6. Another command
is sent that configures the Digital Input for pull-
up configuration. In the pull-up configuration, an
open switch (leak detected) input produces a +5
VDC input at TB7-5 (see below).
•
FLOAT - Enables the float sensor Digital Input
and displays the leak status, as reported by the
float leak sensor, via the Motor Monitoring Board
serial communications. The microboard com-
mands the Motor Monitoring Board to read the
sensor input at TB8-4,5,6.
The optical sensor contains a switch that is connected
between TB7-5 (input) and TB7-6 (GND). With no
leak being detected, the switch closes producing a less
than 1 VDC input at TB7-5, as measured to TB7-6.
When a leak is detected, the switch opens producing a
+5 VDC input at J7-5, as measured to TB7-6.
The Float Sensor contains a switch that is connected
between TB8-5 (input) and TB8-4 (+24 VDC). With no
leak being detected, the switch closes pro24
VDC input at TB8-5, as measured to TB8-6. When a
leak is detected, the switch opens producing a less than
1 VDC input at TB8-5, as measured to TB8-6.
An LED status indicator, labeled Motor Cooling Coil
Leak Detected appears on the MOTOR DETAILS
Screen. It illuminates when a leak is detected.
If the Motor Cooling Coil Leak Detector has registered
a fault condition for at least 3 continuous seconds, a
safety shutdown is performed and Motor Cooling Coil
Leak is displayed. The chiller can be started after the
leak sensor no longer indicates a leak and the COM-
PRESSOR switch is placed in the Stop-Reset position.
