Reader Wiring - HID Mercury MR52-S3B Installations And Specifications

Powering
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2.3 Reader wiring

Each reader port supports a reader with TTL (D1/D0, Clock/Data), F/2F, or 2-wire RS-485 signaling. Power to the reader
is selectable: 12 V DC (VIN must be greater than 20 V DC), or power is passed-through (PT) from the input voltage of the
MR52 (TB7-VIN), 300 mA maximum per reader port. Readers that require different voltage or have high current
requirements must be powered separately. Refer to the reader manufacture specifications for cabling requirements. In
the 2-wire LED mode the buzzer output is used to drive the second LED. Reader port configuration is set via the host
software.
To fully utilize each reader port:
TTL signaling requires a 6-conductor cable (18 AWG).
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F/2F signaling requires a 4-conductor cable.
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RS-485 signaling requires two 2-conductor cables. Use one cable for power (18 AWG) and one cable for
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communication (24 AWG, with drain wire and shield).
Note:
For OSDP cable lengths greater than 200 ft (61 m) or EMF interference, install 120Ω +/- 2Ω resistor across
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RS-485 termination ends.
Data 0 and Data 1 wires for Wiegand may be reused for OSDP. However, standard Wiegand cable may not meet
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RS-485 twisted pair recommendations. The reuse of cable works best on shorter cable lengths at lower data
rates.
J1 – Reader port power select
12V PT Reader power
12 V DC is available on reader ports (VIN > 20 V DC)
VIN power is "Passed Through" to reader ports
Caution: If the input voltage to the MR52 is 12 V DC, jumper J1 MUST be in the PT position.
Input power Reader power select
24 V DC Pass-through
24 V DC 12 V DC
12 V DC Pass-through
12 V DC 12 V DC
PLT-06451, A.1
HID® Mercury™ MR52-S3B Reader Interface
Reader output
24 V DC
12 V DC
12 V DC
0 V DC
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Installation and Specifications
Notes
Caution: Do not use
September 2023