Skip to main content

Hi,  I have been using my AIU to switch certain isolated track section on and off. Recently it hasn't worked.  When I select the accessory on it comes on for a second and then goes off.  I hear the AIU click and engine number boards light up for a second and then nothing.

 

The power that controls the tracks through the AIU is from Variable 1 which is set at Fixed 18V. The track the is not powered through the AIU but also uses Variable 1 is working fine at 18V.

 

Any ideas?

 

 

Thanks Erik

Original Post

Replies sorted oldest to newest

First, you need to press the "ON" soft key, not the "ACT" soft key. "ACT" is a momentary switch.

 

If you are exceeding the 4 amp limit on AIU ports, you don't need anything other than an external relay that can handle 10 amps.

 

This is discussed in considerable detail on pages 87-88 of The DCS O Gauge Companion 2nd Edition, under Controlling Track Power Using the AIU.

 

This and a whole lot more is all in "The DCS O Gauge Companion 2nd Edition", now available for purchase as an eBook or a printed book from MTH's web store site! Click on the link below to go to MTH's web page for the book!

 
 

Todd,

Does MTH have a specific relay to use with the AIU to control blocks? 

To the best of my knowledge, no. Regardless, any relay that can handle the amp load on the siding and for which you have an available power source will do just fine.

 

For example, if you have a siding with 10 amps worth of engines and cars, and a Z4000, you would ideally get a 10 amp relay that's powered by either 10 volts AC or 14 volts AC, since that's what's available from the Z4000's accessory terminals. This should be considerably less expensive than a Lionel BPC or SC-2, both of which are overkill for this application, and both of which can only be operated under TMCC or Legacy.

I would use a DC relay because they are cheaper. With a bridge rectifer wired to the 14 v AC Hot pin. The common would go the the AIU. The relay in the AIU would control the relay that controls the siding. Normally Open would be the track Hot. The wiper would come from a TIU channel.

 

A radio shack relay costs about $6.

 

This way the AIU never sees the track voltage.

Last edited by F&G RY

Same relay at Digi-Key will be a similar price. And always in stock.

Digi-key has an excellent parametric search tool as well.

Just make sure you buy enough to cover the shipping and handling. there may also be a minimum.

I buy through my work so I can avoid these add ons, I just tack my needs onto the next order going out & pay for them.  Working for a small company has some odd benefits.

Post
The DCS Forum is sponsored by

OGR Publishing, Inc., 1310 Eastside Centre Ct, Suite 6, Mountain Home, AR 72653
800-980-OGRR (6477)
www.ogaugerr.com

×
×
×
×
Link copied to your clipboard.
×
×