Interface - GE T35 Instruction Manual

3.3 DIRECT I/O COMMUNICATIONS
a) DESCRIPTION
The following figure shows the 64K ITU G.703 co-directional interface configuration.
AWG 22 twisted shielded pair is recommended for external connections, with the shield grounded only at one end. Con-
necting the shield to Pin X1a or X6a grounds the shield since these pins are internally connected to ground. Thus, if
Pin X1a or X6a is used, do not ground at the other end. This interface module is protected by surge suppression devices.
3
The following figure shows the typical pin interconnection between two G.703 interfaces. For the actual physical arrange-
ment of these pins, see the Rear Terminal Assignments section earlier in this chapter. All pin interconnections are to be
maintained for a connection to a multiplexer.
Figure 3–25: TYPICAL PIN INTERCONNECTION BETWEEN TWO G.703 INTERFACES
Pin nomenclature may differ from one manufacturer to another. Therefore, it is not uncommon to see
pinouts numbered TxA, TxB, RxA and RxB. In such cases, it can be assumed that "A" is equivalent to "+"
and "B" is equivalent to "–".
NOTE
b) G.703 SELECTION SWITCH PROCEDURES
1. Remove the G.703 module (7R or 7S):
The ejector/inserter clips located at the top and at the bottom of each module, must be pulled simultaneously in order
to release the module for removal. Before performing this action, control power must be removed from the relay.
The original location of the module should be recorded to help ensure that the same or replacement module is inserted
into the correct slot.
2. Remove the module cover screw.
3. Remove the top cover by sliding it towards the rear and then lift it upwards.
4. Set the Timing Selection Switches (Channel 1, Channel 2) to the desired timing modes.
5. Replace the top cover and the cover screw.
6. Re-insert the G.703 module Take care to ensure that the correct module type is inserted into the correct slot position.
The ejector/inserter clips located at the top and at the bottom of each module must be in the disengaged position as
3-22
G.703
CHANNEL 1
SURGE
G.703
CHANNEL 2
SURGE
Figure 3–24: G.703 INTERFACE CONFIGURATION
X 1a
Shld.
X 1b
Tx -
G.703
X 2a
Rx -
CHANNEL 1
2b
Tx + X
X 3a
Rx +
X 3b
SURGE
X 6a
Shld.
X 6b
Tx -
G.703
Rx - X 7a
CHANNEL 2
X 7b
Tx +
X 8a
Rx +
X 8b
SURGE
T35 Transformer Management Relay
X 1a
Shld.
X 1b
Tx –
X 2a
Rx –
X 2b
Tx +
3a
X
Rx +
X 3b
X 6a
Shld.
X 6b
Tx –
Rx – X 7a
X 7b
Tx +
X 8a
Rx +
8b
X
831727A2-X1.CDR
X 1a
Shld.
X 1b
Tx -
G.703
X 2a
Rx -
CHANNEL 1
2b
X Tx +
X 3a
Rx +
X 3b
SURGE
X 6a
Shld.
X 6b
Tx -
G.703
X 7a Rx -
CHANNEL 2
X 7b
Tx +
X 8a
Rx +
X 8b
SURGE
831727A2.CDR
3 HARDWARE
3.3.4 G.703 INTERFACE
GE Multilin