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Originally Posted by Mwebb.NJ

Thanks for the reply. I really should sit down and work on BEST program for it, the valves are supposed to be a 1/3 - 2/3 steam pre-heat on a 100% OA AHU. 1/3 valve opens, if discharge air set point isn't maintained 1/3 valves closes and 2/3 valve opens. If more heat is needed 1/3 begins to open again. As far as I know Carrier FID's and CC6400 controls couldn't do this so they just sequenced one valve after the other.

It looks like Atkinson Electronics has a 1 AI => 2 sequenced AO that should work out for now. Time to dust off my BEST++ program manual...

Good day Mwebb.NJ,

You are most welcome and that is great that you found a solution! Indeed, your application was very similar to our customer's application that we designed our device for. In their case their controllers were short an AO and so the time and cost to upgrade all of their controllers was an issue. Designing up what we did saved them a lot of $$$ and more importantly allowed them time to plan on a suitable upgrade path.

Cheers,

Sam

Originally Posted by orion242

So they had a programmable controller and rather than use two outputs, they came up with this Rube Goldberg idea? Seems like more work than just figuring out the programming required and what a PITA to tune.

The Controller in place now is a Carrier CC6400, if I used 2 analog outputs the valves would open and close at the same time instead of one after the other. The CC6400 is a great controller, the standard algorithms can do almost anything you would need. For everything else you can write a custom program with BEST++.

So they had a programmable controller and rather than use two outputs, they came up with this Rube Goldberg idea? Seems like more work than just figuring out the programming required and what a PITA to tune.

Originally Posted by s2sam

Good day Mwebb.NJ,

If you are unable to find anything send me a message, as we designed a very similar device for a customer and so we may be able to adapt the components to do what you want.

Cheers,

Sam

Thanks for the reply. I really should sit down and work on BEST program for it, the valves are supposed to be a 1/3 - 2/3 steam pre-heat on a 100% OA AHU. 1/3 valve opens, if discharge air set point isn't maintained 1/3 valves closes and 2/3 valve opens. If more heat is needed 1/3 begins to open again. As far as I know Carrier FID's and CC6400 controls couldn't do this so they just sequenced one valve after the other.

It looks like Atkinson Electronics has a 1 AI => 2 sequenced AO that should work out for now. Time to dust off my BEST++ program manual...

Originally Posted by Mwebb.NJ

Can anyone recomend a good voltage sequencer? I have a Neptronic TS-MM voltage sequencer with a bad output. I need to take one 0-10vdc input and scale it to control two 0-10vdc outputs. So 0-5vdc input signal transmits 0-10vdc for output 1, and 5-10vdc input signal transmits 0-10vdc for output 2. I did some searching but I'm having trouble finding what I need. Any direction would help me out a lot. Thanks

Good day Mwebb.NJ,

If you are unable to find anything send me a message, as we designed a very similar device for a customer and so we may be able to adapt the components to do what you want.

Cheers,

Sam

I'll look into both of those, Thank you. The Control signal comes from a Carrier CC6400, unfortunately none of the standard algorithms fit my needs. Im sure a custom BEST++ program would achieve the same results as the sequencer but my BEST skills are mediocre at best. Pun intended

ACI has a lot of different transducers and rescalers but not sure if they have one that will rescale each put output differently.

Atkinson Electronics in Murray,Utah can build you anything and they probably already have a board that does that.

Adjustable Voltage Sequencer replacement options

Can anyone recomend a good voltage sequencer? I have a Neptronic TS-MM voltage sequencer with a bad output. I need to take one 0-10vdc input and scale it to control two 0-10vdc outputs. So 0-5vdc input signal transmits 0-10vdc for output 1, and 5-10vdc input signal transmits 0-10vdc for output 2. I did some searching but I'm having trouble finding what I need. Any direction would help me out a lot. Thanks