Trane CVHE Classic Black and -8.25VDC

[chiller rob]

Gents,

I have a customer that was having some star delta starter problems and subsequently went with a benshaw soft starter... we had to get creative with current feedback to the CCM-U1, to get the proper current feed back for FLA. -8.25VDC @ 100. no biggie... units been running great...

3 years later he is having some problems with the control panel.. unit not loading on startup until the vane operator is placed in manual load and then back to auto and it will work. checked chilled water sensor ok, and first stage of freeze stat is ok...

He was sold a upgrade for the CCM U1, turns out it is a MOD 182... this is a physically larger controller and you have to drill a 3rd 1/4 hole for mouniting and the knobs are smaller... also part of the kit is a new chilled water sensor...

The installation instructions are the same as Mod 12... and yes i have upteenth times checked my dip switches...

problem...

1. the new controller is not seeing my -8.25 VDC feed
back from the starter at V1,V2 in the new panel... worked fine in the old one...

2. the new controller by what i am reading is looking for -0-10 VDC @ 100 FLA...

3. I tested the circuit with a 9 volt battery with the demand limit set at 70% machine unloaded with new control.

4. the benshaw A/O is weak and the scale is wide at 0-10 vdc for 0 - 200% amps...

Factory said that they were having problems with this panel recieving the signal from the black box (which i no longer have) and had a converter component that rescaled the signal and amplified it so the new CCM would see it...

I have looked in all my files and I dont have anything on this...

The only thing I could find was the CH 531 starter retrofit kit...

Has anyone seen this before? This is in a critical health care facility any help apprecieted...

Thanks...

[jayguy]

is this KIT09437? are you using bulletin PART-SVN82C-EN?

i am not familiar with what you have or exactly what you are doing. so, do you still have the AGM? i am a little (maybe a lot) confused. i think that you have written things out pretty well...i am just not picturing it well.

let us know.

good luck.

[chiller rob]

yea it is hard to write all this out and i have not learned all the part #'s yet...

the kit that you are talking about, i think, is the Y Delta starter conversion for replacing the black box "motor protector" to a ch 531 controller...

the work i am doing is in the control panel... replacing the capacity control module...

in short, it is looking like, the signal for the old module needs to be rescaled and amplified in order for the new module to get current limit...

thanks...

[jayguy]

it appears that the 2K40 (TRR01860) is a signal conditioner that converts the signal from the 2A54 Dual Analog I/O board from 2-10 to -8.25.

that is if you are using the new CH530/531 type of control to V1 and V2.

good luck.

[chiller rob]

thanks jayguy...

being that the benshaw has a 0-10vdc output for 0 - 200% of amps, instead of rescaleing with a resistor i am going to use a kele dc -dc transmitter.

so i am going to take the benshaw 0 - 10 which would be actually be 0 -5 for 100% FLA and scale with the transmitter a 0 - 10 input to v1,v2...

i know its confusion at its best...

thanks... Rob

[stickerhead]

Call me, I might have a SSOL laying around if you need the signal. I did one in 1997 on a 4160 autotransformer where I installed the black box just for the signal. I did not use it for any other function. Supprised Tim does not have one in his garage! We just bid the CH531 starter retrofit to a school district this week.

[chiller rob]

thanks stickerhead...

the black boxes used be in the way all the time... lately there getting hard to find...

i think this conversion card will work good... we will know on monday...

cheers!

[chiller rob]

stickerhead...

thanks i will take you up on that if we get into a jam... i think our plan is going to work out...
we will know on monday...
those black boxes are getting hard to find...

rob