EMX MRD-1P Manuals & Support

EMX MRD-1P

The EMX MRD-1P is a single-sided radar presence sensor for barrier arm operators. It sees people and vehicles in the path of the arm and holds or reverses the arm.

The detection range is set from 1 to 30 ft on a 3-digit display, and the sensor ignores anything past that distance. Rain, snow, fog and sunlight do not affect it.

Identify your model

The MRD-1P (EMX-1200-1) mounts on a ball and socket bracket with a 1/2 in conduit connection. A 3-digit display and +/- buttons are inside the cover.

Key specs

Technology Radar, single-sided
Range 1 to 30 ft, programmable
Beam width About 2.5 ft at 15 ft, 4.75 ft at 30 ft
Power 6 to 40 VDC or 12 to 24 VAC, 40 mA max at 24 VDC
Relay 1 Form C presence
Relay 2 Pulse on entry or exit
Response time 30 ms
Housing NEMA 4X, 1/2 in NPT conduit thread
Operating temperature -40 to 140 °F

Manuals and documents

Installation Manual

Spec Sheet

Troubleshooting

After power up the Power and Chirp LEDs should be on and the Error LED off. The Presence LED lights when something is inside the set distance.

Presence LED stuck on

  • The sensor may see the ground. Make sure it is not angled down, or mount it higher.
  • Remove columns, curbs or other objects from the detection zone.

Presence shows when the arm is down

  • The beam is reflecting off the arm. Angle the sensor away from the arm and remove flat surfaces on the arm that face the sensor.

Erratic or missed detection

  • Erratic with nothing there: raise the threshold (thr).
  • Drops out while an object is present: lower the threshold, raise the off delay (dLy) or raise transmit power (tPr).
  • Sees things off to the side: lower transmit power.

Display codes

  • E1: a user setting is invalid. Adjust the settings or do a factory reset.
  • E2: internal sensor fault. The sensor needs service or replacement.

Common questions

Mount it beside the lane so the beam crosses the path under the arm. Keep it from angling down at the road or toward the arm itself.

Press + or - on the display. Each press changes the distance by 0.5 ft. The factory setting is 10 ft.

No. It is single-sided radar, so nothing is needed on the other side of the lane.

The FS setting controls the presence relay on power loss or a sensor fault. Check it matches how your operator reads the input.