ACRD 101 cooling unit issue

[shahzad.engr123_apc]

Dear all,

I hope you will be fine. I am facing following issue in Inrow cooling unit of ACRD10. I need the your suggestion and support on this issue, Please do let me know, I will wait for your kind response.

Detailed logs are below mentioned.

APC | Data Log

Date	Time	Operate	Compressor	SupplyAir.C	ReturnAir.C	RackIn.C	Superheat.C	SctnTemp.C	SctnPresr.KPa	DschrgPresr.KPa	FilterDP.Pa	CoolDmd.kW	CoolOutput.kW	AirFlow.L/s	FanSpd.%	OHEInput	OHEOutput	HGBValvePos.%

Regards

• InRow RD 10KW: Compressor did not start exists.

[BillP]

Hello Muhammad. For this error, the compressor is not turning on when it is called for. A HVAC tech would need to check out the compressor to make sure it is good and also check the start capacitor to make sure it is the proper microfarad rating. Also check that the contactor for the compressor is getting the proper 208 volts to pull in. You can contract your local tech support to confirm the readings on the unit to help determine what is keeping the compressor from turning on. 

Thank you

[shahzad.engr123_apc]

Dear Team,

I did the following steps...

• Checked the compressor winding resistance about 2.1Ohm
• Rating of capacitor which is looking good not physically swell.
• Input at compressor contractor is 228V.
• I have replaced th mother board with another running unit, that board is working good on this unit but is board is not working to any other unit.
• Then i upgraded the updated firmware 0f 3.7.4

Will you please guide me how to check this board?

Will you guide me where is the option of SERVICE MODE so that i will be able to reset this mode? might be its service mode is enabled.

I will wait for your response.

Thank you for your kind cooperation.

Regards

MS

[shahzad.engr123_apc]

Still waiting for your kind response.

Regards

MS

[BillP]

Hello. When you checked the ohm readings on the compressor, what did you get from s-c, r-c and s-r? Was the contactor pulling in when the unit was calling for the compressor to run? Is the compressor getting hot at all?

Thank you

[shahzad.engr123_apc]

I got the following readings

s-c=2.1Ohm

r-c=2.2Ohm

s-r=2.1Ohm

Motherboard is not sending the command to pull the contactor for the compressor to run, When compressor is not running then obviously it will not get hot.

I replaced the motherboard with other motherboard then this same unit is working fine.

Please guide me how to check motherboard, Is there any option of SERVICE MODE to reset the compressor command.

Please find the attached unit status report.

Your quick reply will be highly appreciable.

Regards

MS

[shahzad.engr123_apc]

Dear team,

Can you share some kind of FSB or MOS documents.

Reagrds

MS

[shahzad.engr123_apc]

Still waiting for your kind support

[BillP]

Hello. I am sorry about the delay. I would like to make sure, was it just the motherboard that was replaced or was it the motherboard with all the cards on the motherboard as well to get the unit working? I ask because the signal to turn on the compressor comes from the xa card that is connected to the motherboard in slot 1. If just replacing the motherboard caused the unit to run fine, then I would think we had a loose connections on one of the plugs. Check plug 12 and reseat the xa card (slot one on the old motherboard) to see if it was a loose connection. If all the cards were changed, try just swapping out the xa card (slot one) with the old one and see of the compressor will run. If it does not then the relay on the xa to turn on the compressor is bad. The xa card would need to be replaced. Unfortunately there is no service mode in these units to turn on the compressor manually.

Thank you

[shahzad.engr123_apc]

Hello...

Thank you for your prompt response. i got your highlighted points, i will visit couple of days to verify these points then will inform you with updates.

Regards

MS

[shahzad.engr123_apc]

Dear Team,

Sorry for delay. Today i checked the unit as per your instruction,

• I had replaced the xa card with other unit and check the connector plug J12. But there is no loose connection and there is no issue of xa card which is working fine on other unit.
• Kindly tell me is there anymore troubleshooting is remaining to diagnose and resolve the issue or not.
• Updated logs are also attached.

Please check the logs complete of let me know any further troubleshooting.

Regards

[BillP]

Hello. Check the control side of the contactor and see what the voltage is there. Is the contactor pulling in at all? I would request if you can call in when you are with the unit to your local tech support as they can walk through checking where we are losing the voltage to start the compressor.

Thank you

[shahzad.engr123_apc]

Dear Team,

Voltage has been checked by manually volt meter which was 230VAC. But magnetic contactor was not pulling in, even controller board is not sending signal to contactor to pull in.

Regards

MS

[BillP]

Hello. If we have 230V at the control side of the contactor (on a and b) and it is still not pulling in, then we have a bad contactor which will need to be replaced.

Thank you

[shahzad.engr123_apc]

Hello, I think generally mother board sent the command to magnetic contactor to pull in. But  at this issue no commands comes from mother board thats why compressor unable to start. Am i right????

[BillP]

Hello. The motherboard sends a signal to relay 400 to pull in the contactor. Per the picture below, if we are getting 230 volts across 70-4 and 70-6 then the relay is getting pulled in and the contactor is bad. If we are not getting the 230V at these points then we will have to go backwards and find out where we are losing the control voltage to the contactor. See the attachment below.

Thank you

[shahzad.engr123_apc]

Dear team,

Please tell me, can we exchange or replace the mother boards or ACRP102 to ACRP501 or ACRC 103 to ACRD101? Is unit can be operational by this replacement or not???

Regards

[BillP]

Hello. The motherboards are the same on all the Inrow units, however the cards and jumpers that are plugged into the motherboards are different on some of the units. You will need to make sure to keep all the cards and jumpers with the proper unit when swapping the motherboards.

Thank you

[shahzad.engr123_apc · Accepted solution]

Thanks for your usual support