Not receiving 24V signal on IO cable RC7 (Mini I/O)

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If you are using the Mini I/O cable and are not able to read a 24V coming out it could be related to several issues.

Related Error codes:
Error Codes

Diagnostic #1: Determine if you are using external power mode.

Step 1:

Select I/O tab (F4)

Step 2:

Select Aux tab (F6)

Step 3:

Select Int/Ext tab (F4).
Is controller set to internal or external?

Diagnostic #2: Is controller setup for NPN/PNP?

Step 1:

Pictures show a board that is currently setup for NPN.
Is controller set to internal or external?

Step 2:

Check fuses on I/O board.

Step 3:

Check IC chips on board. New robot system comes with 2 new IC chips.

– For PNP type you need IC M54564P (410077-0020)
– For NPN type you need IC M54522P (410077-0010)

Diagnostic #3: Confirm Mini I/O pinout

Step 1:

Please visit DENSO Wave website:

You will need to register if you don’t have a login. Download the RC7 user manuals and look for Mini I/O (CN 5) pin out. Please confirm all wiring of the 24V circuit.                

***If external power is used check and confirm all wiring of external device.       

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