User's Manual

NOTE: WHEN USING AN EXTERNAL POWER SUPPLY, ALWAYS USE A LINEAR POWER

SUPPLY, DO NOT USE SWITCHING POWER SUPPLY.

4.5 Power Supply

The operating frequency of a typical switching power supply ranges from 15 KHz to 50 KHz. It

will usually generate wideband switching noises plus some of its harmonics may fall on or near

125 KHz, the operating frequency of the Reader. Therefore, avoid using a switching power

supply at all times. AVOID using a single power supply for Reader and the magnetic lock.

Doing so will affect the Reader operation and can damage the Reader.

4.6 Grounding

Grounding is critical for proper operation of the Reader. When installing the Reader, it is crucial

to assure that the earth ground is the best ground available. If you elect to use the AC main

power ground, conduct a test by measuring its resistance relative to a known good ground, such

as a cold water pipe or a structural steel that is in direct contact with the ground. The resistance

should be less than 50 ohms. If you find that the AC main power does not provide adequate

earth ground, try using a solid connection to a cold water pipe.

For multiple Readers installation, it is critical that all Readers are connected to the same

grounding system. Using different grounding systems will create secondary current paths or

ground loops that can affect the performance and cause damage to the Reader.

4.7 Wiring Diagrams

The Reader is designed for Wiegand and RS-232 standard communication formats; use Figure

5.2-1 for Wiegand format installation and Figure 5.2-2 for RS-232 format installation, and Figure

5.2-3 for combined Wiegand and RS-232 installation. If an external power supply is being used,

leave the Panel’s Ground and Power terminals open and connect the Reader’s Ground (Black)

and 5-12VDC (Red) terminals to the external power supply.

5.0 INSTALLATION PROCEDURE

Check to verify that every item listed under Section 5.1 of this manual is present before starting

the installation.

5.1 Parts List

a. Installation sheet, P/N: 004-97-A QTY=1

b. Sentinel-Prox MR-1824 Reader, P/N: 004-20-A QTY=1

c. #6-32 x 1” Thread-cutting screw, Type 23, P/N: 616PPN23ZP QTY=4

d. Screw hole plug, P/N: 004-27-A QTY=5 (1 spare)

AWID PROPRIETARY