Keri Systems MR52 - Manual (Page 2)

Mercury Security Corporation © 2011 MR52 DOC 10107-0015 REV 2.02 Page 2
12 TO 24Vdc
GND
VIN
+
-
TB7
2. Supplying Power to the MR52:
The MR52 accepts 12 to 24Vdc for power on TB7. Locate the power
source as close to the MR52 as possible. Make power connection with
minimum of 18AWG wires.
Observe POLARITY on VIN!
3. Communication Wiring (SIO Communication Port):
The MR52 communicates to a Mercury Security intelligent controller (EP2500 for example) via a 2-wire
RS-485 interface. The MR52 allows for multi-drop communication on a bus of up to 4,000 feet (1,200 m).
Use twisted pair(s) (minimum 24AWG) with shield for communication. See specifications section.
Install jumpers according to the selected configuration.
4. Reader Wiring:
Each reader port supports a reader with TTL or RS-485 interface. Power to the reader is selectable:
12Vdc, or input voltage passed through (PT), 125mA maximum per reader port. This selection is made
via jumper J2 and is made for both reader ports. For the selection of 12Vdc, the MR-52 must be powered
by a 20Vdc minimum source. For readers requiring a different voltage or current capability, they must be
powered separately.
To fully utilize each reader port, a 6-conductor cable (18AWG) is required when TTL signaling is used.
RS-485 signaling requires two 2-conductor cables. One cable for power (18AWG) and one cable for
communication (24AWG). Reader port configuration is set via host software.
TR+
TR-
R+
R-
GND
2W
4W
2-WIRE
TB6
(ONLY 2-WIRE RS-485 IS SUPPORTED)
DATA1/DATA0 – CLOCK/DATA 2-WIRE RS-485
RED (1)
WHT (3)
GRN (2)
BRN (4)
BLK (6)
ORG (5)
VO
LED
BZR
D1/CLK
D0/DAT
GND
MR-10/20
READ
ER
ADDRESS 0
MR-DT
RS-485 MODE
9600 BAUD
READER PORT
2-WIRE RS-485
12Vdc (RED) (1)
TR+ (BLUE) (3)
TR- (GRAY) (4)
GROUND (BLACK) (2)
VO
LED
BZR
D1/CLK
D0/DAT
GND