AIU problem - Help please

What are you using to power the accessory on the AIU?

12 volts from the transformer (ZW-L). Only thing connected to that side. Lights fine when no AIU.

If you move the wire from terminal 1 to terminal 2 of the same ACC port the lamp should immediately come on.  Then, when you activate the ACC port and hear the relay click, does the lamp turn OFF?  That is, using terminal 2 instead of terminal 1 should reverse the behavior so lamp turns OFF rather than ON when that ACC is activated.

Presumably you hear the relay click when the ACC is turning ON and separately when you turn it OFF. When you turn it ON take the pair of wires going to that ACC port and move the pair to the other 9 ACC port and see if any turn ON.  This should go pretty quickly taking just seconds since you don't have to screw the wires in...just make intermittent contact to see if the lamp flashes or flickers or whatever.  The idea here is to see if perhaps the "wrong" relay is firing. 

Just for the record, what TIU version are you using?  Your symptoms don't match, but there briefly was the "sticky relay" AIU issue; but that came and went years ago. 

Okay, spent some time playing with relays. Interesting results.

Acc 1, 9, nothing fires when push off; it does when push on

Acc 2, 3, 8,  10, fire when pushed on and off

I did not try 4, 5, 6, or 7

Nothing comes on when connected to terminal 1 and the middle. The bulb lights when wires are connected to middle and 2 on all.

Oddly enough, with Acc 1, neither 1 or 2 fires unless I first push acc 2 on and from. The bulb sometimes comes on. Only place where this happens.

I am not sure what version the TIU is. It is less than two years old. The remote is 6.1.

It looks to me like something is wrong with the AIU. Your Thoughts?

Agreed. Symptoms suggest AIU. The TIU update that fixed the AIU relay issue I'm thinking of was several years ago - version 4 or so.  Warranty ought to take care of it being new.

Bill Webb posted:

 

I am not sure what version the TIU is. It is less than two years old. The remote is 6.1. 

There is probably something wrong with the AIU, but one more thing you might want to check is to be sure the DCS version on the TIU matches the Remote's version 6.1. They should both have the same versions or unexpected results can occur (as in odd behavior).  I have no first hand experience with this so I don't know what 'unexpected results' to expect, but it's been discussed many times here on the forum as causing 'unexpected results'.  

Is not the AIU only a momentary switch? It seems I read that it does not latch to hold current. I could be wrong so correct me if I am. 

patternpilot posted:

Is not the AIU only a momentary switch? It seems I read that it does not latch to hold current. I could be wrong so correct me if I am. 

AIU has 10 SWitch ports and 10 ACCessory ports. 

The SW ports are indeed momentary implemented with relays that fire for exactly 1/2 second when you press the "Straight" or "Diverge" button on the remote.  So this simulates the momentary closures you get from the spring-loaded return-to-center manual lever controllers.

The ACC ports have two modes of operation.  One mode is momentary where the relay closes for as long as you hold down the button on the remote.  The 2nd mode is a latching mode where you press the ON button to activate the relay.  The relay then stays on until you press the OFF button.  Presumably this latter latched mode is what Bill wants.

Here's a short video I made a few years back for an OGR thread showing SW and ACC timing.  Both ACC modes are shown.  

Well, I just learned something. I didn't realize that the accessory could be momentary or locking. I wondered what the button was for that I held down.

Yes, I need the locking.

Actually we are trying to do relays so that we can use more voltage and amps and also control tortoise switch machines from the switch relays. Stan helped me with this months ago and we were ready to start. The first step that I chose was to install the AIU.  It doesn't work so we are stuck until I can pick up some more AIUs in York and give these to MTH. 

But, there is always plenty to do on a railroad.

Thanks for all the help.

Bill