1734-AENTR/C and 1734-CTM Point bus status LED red

[Killercal]

Hello all,

I have a couple 1734-AENTR/C modules (revision 6.012) that are connected to a 1756-L73S (Revision 32.011). I have checked the compatibility and they don't show any issues.

The AENTR chassis has a 1734-IB8S, 1734-CTM and a 1734-OB8.

I have setup the AENTR with the proper IP address and chassis size (4) in the I/O tree and it matches what is in the web browser.

My issue is, when powered up the point bus status LED are flashing red. When I remove the CTM module and adjust the chassis size from 4 to 3 and move the OB8 from slot 3 to slot 2, it works fine.

Has anyone seen this? Any suggestions on how to fix this? Ideally we would like to have the spare slot between the safety card and the output card.

Thanks,

Scott

 

[Killercal]

I ran "Browse Chassis" in the web browser of a rack that has the original that I spec'd and it reports back;
Slot 1 - 1734-OB8S
Slot 2 - 1734-OB8
Slot 3 - Module not found

So it doesn't see the CMT module that is in slot 2.

 

[plvlce]

I have not dealt with 1734-CTM, but based on my experience with 1734-FPD I suspect it is transparent to the data bus and does not occupy a logical slot.

If this is correct, then put the 1734-CTM wherever you want it, but configure the rack as if it did not exist.

 

[Killercal]

I have not dealt with 1734-CTM, but based on my experience with 1734-FPD I suspect it is transparent to the data bus and does not occupy a logical slot.

If this is correct, then put the 1734-CTM wherever you want it, but configure the rack as if it did not exist.

I was just in the works of doing this, and it seems you are correct. It is up and communicating with no Point Bus faults.

Thanks for the response.

 

[Ken Roach]

Exposition:

POINT I/O has several passive modules that provide termination or power only, but do not communicate with the POINTBus or take up a slot number.

Those include:

1734-EP24DC, an Expansion Power module that powers the POINTBus and Field Power Bus, sourced from 24V DC, for larger chassis applications.
1734-EPAC, an Expansion Power module that powers the POINTBus and Field Power Bus, sourced from 120/240V AC, for larger chassis applications.
1734-FPD, a Field Potential Distribution separation module to isolate Field Power Bus sections: AC from DC, or fused from unfused, or sensitive analog from noisy discrete circuits.

There are also modules that only provide extra termination points that tie into the V+ or the Common of the Field Power bus.

1734-VTM is a "Voltage Termination Module"
1734-CTM is a "Common Termination Module"

There are only 8 terminals on a 1734 wiring base, so if you have a 1734-OB8 with eight outputs, the common wires for those circuits have to either be collected at another terminal block, or you can use the 1734-CTM to provide eight terminals to connect them to adjacent to the Output module.

While I think it's counterintuitive, the network adapter is included in the chassis slot count, so your system chassis size is 3.