2.7 Input circuit wiring
There are eight inputs that are typically used to monitor door position, request to exit, or alarm contacts.
Input circuits can be configured as unsupervised or supervised. When unsupervised, reporting consists of
only the open or closed states. When configured as supervised, the input circuit will report not only open and
closed, but also open circuit, shorted, grounded*, and foreign voltage*. A supervised input circuit requires
two resistors be added to the circuit to facilitate proper reporting. The standard supervised circuit requires
1k
Ω
, 1% resistors and should be located as close to the sensor as possible. Custom end of line (EOL)
resistances may be configured via the host software.
*Grounded and foreign voltage states are not a requirement of UL 294 and therefore not verified by UL.
The input circuit wiring configurations shown are supported but may not be typical:
PLT-05246, A.4
15
June 2021
Powering
Trusted Identities
HID Mercury™ LP4502 Controller
Installation and Specifications
