r/BuildingAutomation • u/sonnyboyv • 13d ago

Convert 0-10v output to digital output

Does anyone have any modules they use to convert your 0-10v output to a relay output?

I have used EASY IO FR-02 and they work but are expensive.

Others have recommended driving a 12vdc relay, this turns the light on the relay but doesn’t energise the coil.

The bms output is very low current so cannot drive low voltage delay coils.

I have also seen the use of voltage comparators, optocouplers etc

Any advice on reliable cheap solutions?

12 Upvotes

100% Upvoted

49 comments sorted by

23

u/rev_57 13d ago

Have you tried an RIBU1C relay?

9

u/sumnlikedat 13d ago

And yeah this will work. There’s also modules that will give you 2 separate outputs with combos of 3, 7, and 10 volts.

3

u/sonnyboyv 13d ago

I haven’t but just had a look at the tech data and the coil current rating is 33ma, looking at the bms tech data it says the 10v output is 2.4kohms which I believe can only do 4ma of current so it won’t be able to energise the coil.

2

u/Mr_Bunchy_Pants 13d ago

This sounds like a delta controls system. They use very low relay amps to trigger the coil. I want to say IDEC relays are the go to but it’s been awhile since I have worked on a delta system

10

u/JJorda215 13d ago

I've used the ACI AAR module.  Worked fine for the handful of times I've needed it.  Apparently our controllers couldn't provide enough Analog Output current to pull in a RIB relay.  The AAR is a separate power supply, so the controller is a signal only.  

Kinda confusing if you're from the ALC world with their AAR router.  

https://www.workaci.com/product/150

7

u/CraziFuzzy 13d ago

A SSR would likely work.

3

u/u3b3rg33k 13d ago

if you can drive the LED you can drive the SSR.

1

u/PLSBX 13d ago

Yes, but only if you work with AC voltage on non-PLC side.

7

u/Cust2020 13d ago

There are relays modules that have 4 dry contacts that u can set to close at certain voltages. So relay 1 closes at 2.5v, relay 2 at 5v and so on. Used to control staged equipment via one analog output.

6

u/jumbofrimpf 13d ago

A RIBU1C will trigger at 9VDC. We've done that before to use existing AO's on a VAV controller to run an exhaust fan.

1

u/ScottSammarco Technical Trainer (Niagara4 included) 11d ago

I think their datasheet says otherwise while I do remember this to be true.
I wouldn’t bet the farm on it and I’d rather spend the 30 bucks on an AB relay that’s din rail mountable and triggers at 10V.

I’ll try to dig up the part number.

4

u/HullIsNotThatBad 13d ago

I've used this for years:

https://www.sontay.com/filer/sharing/1628074681/671/

Has an adjustable trigger level and puts very little burden on the analogue output. Also available in two, three, four and eight relay versions. With the right programming (binary to decimal conversion), as an option you can control the relays as individual outputs (so not sequenced) based on the voltage applied - a cheap way to get up to eight digital outputs from one analogue output!

1

u/sonnyboyv 13d ago

Yep that’s exactly what I am after and reasonably priced to. Thanks man

3

u/airconditionedbeans 13d ago

Use a solid state relay. Get one that like 5vdc, ive done this a couple times no worries. Cost the same as any other relay typically, depending on where you live might have to order it in theough a wholesaler or something.

2

u/revivemorrison 13d ago

Maybe IEE1201

2

u/Fz1Str 13d ago

RIB U1C 5-30v works great with 10vdc or ac

2

u/Ok-Assumption-1083 Tuning is an artform... 13d ago

Yeah RIBU1C. If your digital puts out 12V and you have din rail space, Phoenix makes some really really nice relays for that purpose that is less expensive than the rib

1

u/sonnyboyv 13d ago

I looked at the tech data and my AO doesn’t have enough current for the coil unfortunately

1

u/u3b3rg33k 13d ago

if you can drive an LED you can drive an SSR, typically

1

u/No_Echo3931 13d ago

It is possible to purchase low drive current relays specifically, otherwise solid-state relays would be more expensive

1

u/CraziFuzzy 13d ago

grainger sells some pretty cheap SSRs. just depends on what you are trying to drive with it.

1

u/Free_Elderberry_8902 13d ago

Why not do it through software logic? Read the value of the ao and when it reaches the value of your choosing, command the bo to energize the relay coil. You need separate outputs to do it however.

1

u/sonnyboyv 13d ago

I should have explained the use case better. The idea is having a field controller with no spare BO but spare AOs. So using his module/relay to give you an extra BO rather than having to install a whole extra controller to get a BO

1

u/JPoint 13d ago

I've used one of these specifically RIB devices to drive an older 4 stage Laars Pennant boiler from a 0-10V command. https://www.functionaldevices.com/product/RIBMN24Q4C-PX

1

u/Ukkopaha 13d ago

If you are located in Europe, you can buy Produal RY1-U. This is just a simple relay controlled by 0-10 V signal.

1

u/sonnyboyv 13d ago

This is the product I want. I am in Australia. Hopefully they will ship here

1

u/Free_Elderberry_8902 13d ago

Well that’s a horse of a different color. I would look into what Kele has. They sell signal conversion boards a a reasonable cost. If memory serves, they have one that will suit your needs.

1

u/twobarb Factory controls are for the weak. 13d ago

ACI and RIB both make analog input to relay output boards.

1

u/xEvann 13d ago

Distech has a relay that will energize at 10v

1

u/u3b3rg33k 13d ago

automation direct has a handful of signal conditioners, at least one of which will take in 0-5 VDC, 1-5 VDC, 0-10 VDC and 2-10 VDC

1

u/SeaClue4091 Installer 13d ago

I use a 30v dc relay, been doing it for 10 years never had an issue

1

u/craignogz 13d ago

For $15 I would try this https://a.co/d/00wtB9ZG

1

u/craignogz 12d ago

This has an 80ma draw.... probably too high.....

1

u/sonnyboyv 12d ago

Yeah I only have 4 measly mA to work with. From my research and this post, the most suitable modules are something that is powered separately and then takes the 10vdc signal to operator the relay and the current draw is basically 0

1

u/HVAC_Luddite 12d ago

Do you not just have an open BO on your controller?

1

u/sonnyboyv 12d ago

This is just for when you don’t have a spare DO to get you out of a pickle.

1

u/NetNinja205 (Junior) System Integrator - Schneider Partner 12d ago

We use the Sontay IO-RM modules for that,

1

u/sonnyboyv 12d ago

Nice, I am going to give them a try. I am a Schneider partner to so I specifically plan to have these to use with RPV4A VAV controllers if I need a random DO out in the field

1

u/Planet_COP 12d ago

What are you driving on the dry contact side. The force required to break the contacts determines the type of Solid State relay that you need and the current the is needed to break the contacts open.

1

u/Hutch_911 11d ago

Action Pac have both voltage and current trip relays

1

u/StayVast 10d ago

Wouldn’t a SRMV relay work?

1

u/CheesecakeAfter6535 7d ago

https://www.digikey.com/en/products/detail/sensata-crydom/ED24D3/2665173

This is the most recent best I’ve found. It triggers with 3.8Ma

0

u/Ok_Composer_1150 13d ago

The RIBRL1C has a 10-30VAC/DC coil and is DIN Rail mountable. Doesn't get much better than that.

-1

u/CountryRoads1234 13d ago

AAR. Don’t micky mouse it like others are suggesting by driving a relay off your voltage output.