SRVO-378: SFDI xx status abnormal
Chain alarm on a safety digital input (SFDI) - the named dual-channel input has one channel open while its partner is closed.
What it means
Chain alarm on a safety digital input (SFDI) - the named dual-channel input has one channel open while its partner is closed. The signal name in the message decodes what tripped: on multi-robot systems, SFDI112/212 through SFDI115/215 map to robot disable switches 1-4 (chain 1/2 respectively). And on Teach Pendant Hot Swap systems, SFDI11/21 alarms are the signature of a pendant connected or disconnected without pressing the disconnect switch.
Common causes
Ranked by what technicians most often find, most likely first.
- Faulty circuitry connected to the dual input - the external device's wiring.
- The dual input's timing out of spec (both channels must switch nearly together).
- Robot disable switch or its cable, when the signal decodes to one.
- Hot Swap procedure violation: pendant swapped without the disconnect switch, or in AUTO.
- Hardware: optional safety I/O board (B-cabinet), emergency stop board; Hot Swap hardware on those systems.
How to fix it
- Do not reset this chain error to keep running until the failure is identified and repaired: with one duplicate circuit faulty, safety is not guaranteed if the other fails. The signal name in the message decodes the source (external device wiring, a robot disable switch, or a teach-pendant hot-swap done without the disconnect switch). Identifying and repairing the specific fault (the connected device's circuitry and channel timing, a disable switch and its cable, or the safety I/O and E-stop boards) is qualified-technician work per the maintenance manual. Recovery afterward uses the SRVO-230/231 chain-release procedure.
Quick facts
- Category
- Servo
- Affected series
- R-30iB; R-30iB Mate; R-30iB Plus; R-30iB Mate Plus
- Alarm family
- SRVO