What causes Okuma OSP alarm 1873?

Faulty front door magnetic (mechanical) lock switch not holding the door closed during loader motion. Cut or broken wire in the door lock switch circuit. Area sensor signal going OFF while the loader is running or being jogged manually with the door not fully closed. Front door not fully closed/latched when loader operation was started.

How do I fix Okuma OSP alarm 1873?

1. Read the code number shown with the alarm: code 1 = Area sensor signal went OFF during automatic loader running with the front door not closed, or the loader began moving while the area sensor signal was already OFF.; code 2 = Area sensor signal went OFF while the loader axis was being run manually with the front door not closed. 2. Read the code shown with the alarm. Code 1: the area sensor signal went OFF during automatic loader running, or the loader started moving while the area sensor was already OFF. Code 2: the area sensor went OFF while the loader axis was being moved manually with the front door not closed. 3. Check that the front door is fully closed and latched; try to pull it open while the loader is in motion — it should be held by the magnetic (mechanical) lock switch. 4. Inspect the wiring to the front door magnetic lock switch for a cut, pinched, or disconnected wire; repair any damaged wiring. 5. Test the magnetic (mechanical) lock switch itself for proper engagement and release; if it does not hold the door closed during loader movement, replace it with a new one as directed by the manual. 6. Verify the area sensor is aligned and its signal stays ON with the door closed; clean or realign the sensor if its output drops intermittently. 7. If the alarm returns after replacing the switch and checking the wiring, record the alarm number, code and object and contact Okuma service.

Okuma OSP codes

axismd.ai

Okuma OSP Controller

Safety · Intermediate

Alarm 1873

Okuma OSP Alarm A 1873 - Door interlock

The control detected that the machine front door was opened, or the area sensor signal dropped, while the OGL loader (or robot) was operating. The front door is supposed to be held shut by the magnetic (mechanical) lock switch whenever the loader is moving, so this alarm means the door interlock chain was broken during loader motion.

Okuma OSPSafetyIntermediate

1873

Okuma OSP Alarm A 1873 - Door interlock

Door interlock

Common Causes

Faulty front door magnetic (mechanical) lock switch not holding the door closed during loader motion
Cut or broken wire in the door lock switch circuit
Area sensor signal going OFF while the loader is running or being jogged manually with the door not fully closed
Front door not fully closed/latched when loader operation was started

Troubleshooting Steps

1Read the code number shown with the alarm: code 1 = Area sensor signal went OFF during automatic loader running with the front door not closed, or the loader began moving while the area sensor signal was already OFF.; code 2 = Area sensor signal went OFF while the loader axis was being run manually with the front door not closed.
2Read the code shown with the alarm. Code 1: the area sensor signal went OFF during automatic loader running, or the loader started moving while the area sensor was already OFF. Code 2: the area sensor went OFF while the loader axis was being moved manually with the front door not closed.
3Check that the front door is fully closed and latched; try to pull it open while the loader is in motion — it should be held by the magnetic (mechanical) lock switch.
4Inspect the wiring to the front door magnetic lock switch for a cut, pinched, or disconnected wire; repair any damaged wiring.
5Test the magnetic (mechanical) lock switch itself for proper engagement and release; if it does not hold the door closed during loader movement, replace it with a new one as directed by the manual.
6Verify the area sensor is aligned and its signal stays ON with the door closed; clean or realign the sensor if its output drops intermittently.
7If the alarm returns after replacing the switch and checking the wiring, record the alarm number, code and object and contact Okuma service.

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