What causes fault code AB-CIP-ERR1 (EtherNet/IP CIP Error — Connection Rejected (16#0111))?

RPI set too low for the target device — device cannot process data that fast. Device firmware does not support the requested RPI range. Too many connections consuming device bandwidth — each connection adds processing overhead. Multicast vs unicast mismatch — device requires one but configured for the other. Module definition in controller uses wrong electronic keying — revision mismatch

How do I fix fault code AB-CIP-ERR1?

In Studio 5000, right-click the faulted module > Properties > Connection tab to see the specific CIP error code. Increase the RPI value — try 20ms, 50ms, or 100ms depending on application needs. Check device documentation for supported RPI range — some devices minimum is 10ms. Verify electronic keying setting — try 'Compatible Module' instead of 'Exact Match'. Reduce the number of connections to this device — consolidate I/O into fewer connections. Update device firmware if RPI range was expanded in newer firmware

EtherNet/IP CIP Error — Connection Rejected (16#0111)

AB-CIP-ERR1

A CIP connection request was rejected by the target device with error code 16#0111 (RPI not supported). The requested packet interval is outside the device's supported range.

medium allen-bradley plc

allen-bradley ethernet/ip cip rpi connection error code

Probable Causes (ranked)

RPI set too low for the target device — device cannot process data that fast
Device firmware does not support the requested RPI range
Too many connections consuming device bandwidth — each connection adds processing overhead
Multicast vs unicast mismatch — device requires one but configured for the other
Module definition in controller uses wrong electronic keying — revision mismatch

Fix Steps

1 In Studio 5000, right-click the faulted module > Properties > Connection tab to see the specific CIP error code
2 Increase the RPI value — try 20ms, 50ms, or 100ms depending on application needs
3 Check device documentation for supported RPI range — some devices minimum is 10ms
4 Verify electronic keying setting — try 'Compatible Module' instead of 'Exact Match'
5 Reduce the number of connections to this device — consolidate I/O into fewer connections
6 Update device firmware if RPI range was expanded in newer firmware

Field Trick

When you get CIP errors and can't figure out why, change the electronic keying to 'Disable Keying' temporarily. If the connection comes up, the issue is a catalog number, revision, or firmware mismatch — not a network issue. Then tighten keying back up once you identify the mismatch.

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