Swaping S5 100U CPU102

I have an S5 100U CPU102 PLC that's playing up, and I need to swap out the CPU at some point.

I have an S5 100U CPU103. Am I correct in thinking that being a higher spec model it will that the place of the 102 just fine, without software mods?

I think you're right in the 103 being af higher spec cpu and will replace the 102. But doing that without software modifications is not a guarantee. If you have the other cpu in stock I would just try an see if it will run. Do you have epprom in the 102 to plug into the 103?

Jonas.

The 102 CPU has 2 modes, Test and Normal. If there is no EPROM fitted it is in test mode. In test mode the program execution is very slow, around 70ms per 1K instructions, normal Mode is around 5ms if I remember correctly. The 103 is faster, so if you have an EPROM module then plugging it into the 103 will work, but reaction times will be a bit faster. If there is no EPROM and you copy the program using step5 then expect a big change in reaction time. If it is a process this may not be such a problem, but if it is a machine there may be positioning issues due to the scan cycle.

Thanks for the replies.

The program is on an EPROM currently in the 102 CPU, so I'm hoping just swapping them over will work