QUANTUM
™
LX EVAPORATOR CONTROL PANEL
COMMUNICATIONS SETUP
090.610-CS (MAY 2016)
Page 115
RS-422 WIRING AND JUMPERS
The following table describes the RS-422 connec-
tor pinouts and their associated communications
signals:
RS-422 (TB1) Signal Wiring
TB1 Connector Pin # Signal
4 TX+
3 TX-
2 RX+
1 RX-
COM-1 (TB1)
The following pictorial shows the communi-
cations board, as well as the jumpers, LED’s
and signal pinouts to allow the end user to
communicate to Com-1 (TB1) using RS-422
protocol. Refer to the tables in this section
for the specics on the jumper settings and
wiring convention for RS-422:
0
1
Com-1 (TB1)
RS-422
RS-422 Com-1 (TB1) Connector, Jumpers and LED Location
RS-422 (TB1) Board Jumpers
LINK POSITION FUNCTION
LK2
In
Out*
Terminate COM1
No termination
RS-422
LK7
In
Out*
Pull down COM1
No pull down
RS-422
(-RX)
LK8
In
Out*
Pull up COM1
No pull up
RS-422
(+RX)
LK9
In
Out*
Pull down COM1
No pull down
RS-422
(-TX)
LK10
In
Out*
Pull up COM1
No pull up
RS-422
(+TX)
LK16
A *
B
COM1 RS-422 (TB1)
COM1 RS-485 (TB1)
* Standard Setting
COM-2 (TB2)
The following pictorial shows the communi-
cations board, as well as the jumpers, LED’s
and signal pinouts to allow the end user to
communicate to Com-2 (TB2) using RS-422
protocol. Refer to the tables in this section
for the specics on the jumper settings and
wiring convention for RS-422:
422 Connector
0
1
PL3
RS-422 Com-2 (TB2) Connector, Jumpers and LED
Location
RS-422 (TB2) Board Jumpers
LINK POSITION FUNCTION
LK 1
In
Out*
Terminate COM2
No termination
RS-422
LK 3
In
Out*
Pull down COM2
No pull down
RS-422 (Rx-)
LK 4
In
Out*
Pull up COM2
No pull up
RS-422 (Rx+)
LK 5
In
Out*
Pull down COM2
No pull down
RS-422 (Tx-)
LK 6
In
Out*
Pull up COM2
No pull up
RS-422 (Tx+)
LK
11
A
B*
Select RS-232 for COM2 (TB3)
Select RS-422 for COM2 (TB2)
LK
17
A * COM2 RS-422 (TB2)
B COM2 RS-485 (TB2)
* Standard Setting