Honeywell SYA14 Series Manual page 199

If a protective safety equipment (FF-LS safety light curtains or machine safety control equipment monitored by the FF-LS)
failure occurs during self-check or test input, the protective safety equipment is locked in an OFF condition. This OFF
condition cannot be defeated by turning the power supply voltage OFF and ON.
Table 5-4 Troubleshooting Chart
Failure
• Sensing field is clear, but the protective
safety equipment will not release after
actuation of an external reset push
button switch.
• Green LED indicator is illuminated.
• Sensing field is clear, but the protective
safety equipment will not release after
actuation of an external reset push
button switch.
• Red LED indicator is illuminated.
• Sensing field is clear, but the protective
safety equipment will not release after
actuation of an external reset push
button switch.
• No LED indicator is illuminated.
• During normal operation the red LED 5,
located near microprocessor on circuit
board in control unit (see figure 5-2),
pulses (illuminates) every 3 seconds.
• If there is no release when the sensing
field is clear, the red LED 5 may:
• Illuminate continuously
• Flicker one time
• Flicker two times
• Flicker three times
• Flicker four times
• Flicker five times
37
Possible cause
• Open circuit between output relays
and machine control circuitry.
• Blown fuse at output relay terminals. • Replace fuse.
• Open circuit between both or one of
the sensing units and the control
unit.
• Translucent surface of sensing units
are contaminated.
• Sensing unit is defective.
• Faulty reset pushbutton or open
circuit.
• No supply voltage to the control
unit.
• Blown fuse at supply voltage
terminal.
• Faulty synchronization
• Faulty self test
• Faulty communication
• Faulty communication sensor A
• Faulty communication sensor B
• Faulty installation parameters
107022-14 EN FR26 GLO 0100 Printed in Germany
Inspect and repair
• Inspect terminal wiring and, if
necessary, repair wiring.
• Ensure correct terminal polarity
and proper cable connection
between the sensing and control
units.
• Clean surface.
• Replace sensing unit (matched
pair).
• Replace reset pushbutton or repair
wiring.
• Inspect terminal wiring and, if
necessary, repair wiring.
• Replace fuse. See fuse
replacement. (5.4.1)
• Replace control unit.
• Replace control unit.
• Replace matched sensor units.
• Visually inspect cable pair and
replace if required.
• Visually inspect sensor cable A
and replace if required.
• Visually inspect sensor cable B
and replace if required.
• Visually inspect compatibility of
sensor and control unit
components. Ensure the beam
number labels on all of the
components are the same.