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4.3.7 S2A-172 (Reverse Polarity Card)
The Reverse Polarity Card is only installed as part of the Reverse Polarity Option Package (Option 217). If
Option 217 was not included, the A75D(E) will not have a Reverse Polarity Card.
The S2A-172 Circuit Card is located towards the top of the door or front panel. Before removing the card
unplug all cables and connectors, make a note of where the cables plug in.
Each connection port on the Card is
labeled; it is strongly recommended to label each cable with the name of the port it connects to.
Remove the
circuit card from the case by simply removing the two screws holding the card to the case and carefully pulling
the board out. Installation is the reverse of removal.
WARNING: Take care to plug all wires/cables into
there correct locations.
4.3.8 Fuses (Reverse Polarity Option)
Fuses are only installed as part of the Reverse Polarity Option Package (Option 217). If Option 217 was not
included, the A75D(E) will not have any Fuses.
The fuse is designed to blow only when the battery is connected incorrectly and should rarely need
replacement. Locate the DC Fuse.
Remove the leads from both sides of the fuse. Use a handheld multimeter
to check that fuse is in fact blown. Install a new fuse in the place of the blown fuse if necessary.
4.3.9 S2A-198B (12V Relay Card)
The Relay Card is only installed as part of the Discrete Alarm Option Package (Option 46R). If Option 46R was
not included, the A75D(E) will not have a Relay Card.
4B75 Case
The S2A-198B is mounted to a bracket located at the top left of the case. If the unit has either DNP3 or
Modbus Option Packages, the S2A-302S card is mounted on the same bracket. Remove the three screws at the
front of the bracket and the two bolts at the back. Before the bracket can be completely removed the ribbon
cables of the S2A-198B will need to be removed (If the S2A-302S card is installed the ribbon cable and power
plug will need to be removed at this time). After the bracket is removed the four screws that hold the S2A-
198B to the bracket can be removed. Installation is the reverse of removal.
WARNING: Take care to plug
all wires/cables into there correct locations.
475/975/72 Case
The S2A-198B is mounted to the front of the card house. Remove the ribbon cable from the S2A-198B card.
Remove the four screws that hold the S2A-198B card to the card house, and gently remove the card.
Installation is the reverse of removal.
WARNING: Take care to plug all wires/cables into there correct
locations.
