As part of your installation, you might need to include a Mercury MR52 interface module.
|A||Reader connections||The wire colors in the illustration refer to "pigtail" HID readers; the information in parentheses refers to "terminal block" HID readers.|
|B||Inputs||Inputs 1 to 8 can be configured to use End-Of-Line (EOL) resistors, and for normally open or normally closed contacts.|
|C||Address switches||Used to set the device address. For more information on address settings on the Mercury module, refer to the manufacturer's instructions.|
|D||Reader power||12V = 12 V dc at readers, PT = voltage “passed through” to
IMPORTANT: For UL294 and ULC-S319 compliant Synergis™ installations, always install the jumper in the PT position.
|E||2W/4W Select||Install jumper in 2W position (4W is not supported).|
|F||Line termination||For end-of-line interface modules, install jumper J5 (MR52) or J4 (MR52-S3) for 120 Ohm line termination (J6 is not used).|
|G||RS-485||RS-485 bus connection to other Mercury modules.|
|H||Relay outputs||6 x Form-C
MR52: 5A inductive @28 V dc, 0.6 PF
MR52-S3: NO: 5A, NC: 3A, inductive @28 V dc, 0.6 PF
|I||Power In||Connect + to VIN (observe polarity). Connect - to GND. Use 20 AWG wires minimum.|
|J||Resistors||For OSDP integrations, prevent readers from misinterpreting noise
on a non-driven RS-485 line as data by installing a 1k ohm pull-down
resistor from D0 to GND on both Reader 1 and Reader 2.
For wiring distances over 10 meters, install a 120 ohm termination resistor between D0 and D1, as well as between A (-) and B (+) on the RS-485 bus of the last connected reader.
To find out whether you need to add 1k ohm pull-down resistor between D0 and GND, see KBA-78953.