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IQH1S 1U Enclosure
SECTION 3
IQH1SOPS
23/11/06
www.snellwilcox.com
Version 1 Issue 4
3.2
COMMUNICATION CONNECTIONS
Remote
This 9 pin `D' connector on the rear panel allows
the unit to be connected to the RollCall 485
network communications system.
Note that RS485 interconnections should be
pin to pin and only be used for Snell & Wilcox
RollNet applications.
This connector may also be used as a RS422 port.
RollCall
This BNC connector allows the unit to be
connected to the RollCall network communications
system.
The RollCall system should be connected using
75 Ohm "T" pieces in a similar manner to an
"Ethernet" system. Both extremities of the system
must be terminated in 75 Ohms.
Note that in a RollCall™ segment, all units must
have different unit address codes.
Note:
The coaxial link is bi-directional and
therefore must not be passed through signal
switching networks. Also, to allow hum and noise
cancellation the screen of the coaxial connection
must not be earthed.
100-240V~
60/50 Hz
1.8A
T
T2A H 250V
ERIAL IN
UT
1
R
O
L
L
C
A
L
L
OUTPUT
IQ
A
V
D
A
-2
4
5
7
8
1
6
2
7
3
8
4
9
5
1
6
2
7
3
8
4
9
5
N.B. Connector is a socket,
viewed from mating face.
Equivalently, this is a plug,
viewed from the rear,
cable face.
Physical Interface - RollCall RS422
For reference, the A signal
is at 0V at line idle, and
the B signal at 5V.
9-Way Ribbon connections
TxA
Pin 2
RxB
Pin 3
GND
Pin 1
TxB
Pin 7
RxA
Pin 8