Accessory 18RX (Relay Expansion Module) provides some commonly used accessory relays to signal normal and emergency source availability. Option Relays OP2 and OP3 can be configured to provide functions such as, load disconnect control (Feature 31), engine start signaling (NR2), and various common alarms.

• Accessory 18RX Kit part number 93514
• Only two Accessory 18RX modules can be installed/connected in a Group G controller.

1. Deenergize the transfer switch. Then open the enclosure door and verify that all power is off.
2. Mount the DIN rail onto two short studs (on the door) below the controller. If a DIN rail is already installed it may have room for the 18RX module.
3. Install the 18RX module onto the DIN rail (left side). Hook the top of the module onto the DIN rail and rock it downward until it snaps in place.
4. Connect the ribbon cable by following a. or b. below:

• a. If an 18RX module is already installed; connect the ribbon cable between the existing 18RX module (J12A) and the 18RX module being installed (J12B). Note: If an Acc. 1UP module is installed and connected to the existing 18RX module, unplug it from the existing 18 RX module and reconnect it to the 18RX module being installed (J12A).
• b. If an 18RX module is not already installed; connect the ribbon cable between the 18RX module (J12A) and the controller (J3). Note: If an Acc. 1UP module is installed and connected to the controller, unplug it from the controller and reconnect it to the 18RX module (J12A).

5. Refer to transfer switch wiring diagram for connections and rating of OP2 and OP3 contacts.
6. After installation and all wiring has been completed, close the enclosure door. Reenergize the transfer switch.

Refer to this link for the Installation Manual for the 18RX Module:
https://www.ascopower.com/us/en/download/document/TS-UM-300ACCESS18RX/

NOTE: ​​​​Accessory 18RX also known as REX (Relay Expansion Module) is an optional accessory for the Group G controller. Up to two 18RX modules can be added to an Open Transition Transfer Switch (3ATS) while only one can be added to a Delayed Transition Transfer Switch (3ADTS) since one REX module is already present on this type switch

If unsure, contact Technical Support at 1-800-800-ASCO or send an email to technicalsupport@ascopower.com

Published for:ASCO Power Technologies USA