Help with AB 1771 analog input card

Hello guys,

I have a PLC 5 here with a 1771 series A analog card that has failed. All we have is a 1771 series C analog card for replacement. The series A card is currently set up for differential current. I can see the series C and series A are physically different but seem to be capable of the same features.

I tried setting the series C up for differential current with the jumpers and plugging it in but the green run light just flashes and the card does not seem to work. Are there any other jumpers on the card I’m missing or does anybody know how to accomplish this transition or if it’s even possible in the first place?

I cannot find anything in the manual pertaining to a green flashing light. I am on site now and any help is appreciate.

-Tex

Did you set the "Emulation Mode" jumper on the top of the module so that it emulates Series A/B ?


The flashing green LED indicates that the module has not received a usable configuration Block Transfer Write (BTW) instruction.

The Series A/B and Series C have different lengths of BTW configuration blocks. Check through the user program for whatever triggers the BTW to set up that module, and what length that block is.

Ken Roach said:

Did you set the "Emulation Mode" jumper on the top of the module so that it emulates Series A/B ?


The flashing green LED indicates that the module has not received a usable configuration Block Transfer Write (BTW) instruction.

The Series A/B and Series C have different lengths of BTW configuration blocks. Check through the user program for whatever triggers the BTW to set up that module, and what length that block is.

Click to expand...

Ken,

I cannot access the PLC as there is not copy of the program and I do not have the RSLogix 5 software, so I'm hooped on that respect. I have set the jumper to position E which to simulate the series A/B card.

I'm guessing I'm screwed without going online unless I can find the same series A replacement card which should be plug and play.

a straw at which to grasp ...

after you replaced the module - did you do a Run>Program>Run cycle (with the keyswitch) or maybe a power cycle? ... note that just going from Run>Remote>Run usually isn't enough ...

reason for asking - if the module is just "plugged in" while the system is running, the program is USUALLY not written to send the BTW to "configure" the module ... that step is USUALLY only done at "start up" or "go to run" ...

you really need a copy of RSLogix5 software if you're going to keep working on the PLC-5 systems ... yes - it's expensive - but sometimes you have to have the proper tools to get the job done ...

the "Series C" manual linked below describes the differences between series A & B - and the newer series C ... it's in Appendix B near the back ...

page 7-3 describes the status lights ...

https://literature.rockwellautomation.com/idc/groups/literature/documents/um/1771-um663_-en-p.pdf

good luck with it ...