Chiller Install, Max Asorption??

[MidgetD]

Hello guys, I am a little cnfused by the manufacturers inf on this one.
I have received a new chiller unit for installation.

Nameplate data is:

480 3phase

Largest motor FLA = 10.88 A

Max Asorption = 14 A

Installed power= 9.2 kw or 10 hp

I do not have a MCA, or MOCP rating. I am ASSUMING the RLA is the max asorption???

Can I use the largest FLA x 175% to get a 20 amp breaker. And 125% x max asorption to get 17.4amps or a minimum wire size of 12awg.

Does this seem correct or am I way off base?

 

[templdl]

Hello guys, I am a little cnfused by the manufacturers inf on this one.
I have received a new chiller unit for installation.

Nameplate data is:

480 3phase

Largest motor FLA = 10.88 A

Max Asorption = 14 A

Installed power= 9.2 kw or 10 hp

I do not have a MCA, or MOCP rating. I am ASSUMING the RLA is the max asorption???

Can I use the largest FLA x 175% to get a 20 amp breaker. And 125% x max asorption to get 17.4amps or a minimum wire size of 12awg.

Does this seem correct or am I way off base?

LRA may be 7-13X the FLA so max absorbtion must not be that. Besides the compressor how about other loads such an fans etc. which could easily be 3a?

 

[MidgetD]

DUTY
Fluid type: 40 / 60 % ethylene glycol/waterFluid flow rate: 8 USgpmFluid inlet temp: 55 ?FFluid outlet temp: 45 ?FAmbient temp: 114 ?FHeat rejection: 3.4 Tons
EQUIPMENT
Model Number: TAEevo 051-UL
Refrigerant: R-407c
Refrigeration Circuits: 1
Compressor Quantity: 1
Compressor Type: Hermetic Reciprocating
Compressor Power: 6.17 kW
Electric Service: 460/3/60 V/Ph/Hz
Fan Quantity: 1
Fan Type: Axial
Fan Power (each): 1.05 kW
Pump Quantity: 1
Pump Type: Centrifugal
Pump Power (each): 0.75 kW
Available Pressure: 40 psig
Inlet / Outlet Connection: 1? NPT
Dry weight: 528 lb
Tank volume: 30 gal.
Dimensions: 26 x 51.6 x 55.1 w? x l? x h?

These are the spec that were sent t me.

Also the LRA of the compressor is labeled 67A with a 15 amp max.

The pump had 1.54 rated amps on the nameplate

Manual defines:installed power= power asorbed by teh unit during th e limit working conditions

max consumption (I max) = electrical current consumed by the unit during the limit working conditions.

higher motor fla = max. asorbed currrent.

 

[MidgetD]

Update

Update

I thought the chiller manufactureer was suppsed t supply the MOCP MCA and RLA values for the equipment. However, this unit was manufactured in Italy and has a little different acronyms I beleive. Anyway , I have found all my FLA and have attempted to do the sizing myself. I am not very experienced with this so I would like any feed back possible.

Compressor FLA= 10.88 amps
Fan 1 FLA= 1.17 amps
pump 1 = 1.54 amps
pump 2 = 2.71 amps

Branch Circut Selction current= 2.71+1.54+1.17+(1.25% x 10.88) = 19.02 amps

Branch circut overcurrent protection calc: 225% of highest FLA or Branch circut selection current whichever is higher

2.25 x19.02 amps(branch circut selectin current) =42.795 amps

therefore max size breaker is 40 amps.

I plan to run 10 awg wire (copper) instead of 12 awg (copper) to match the ampacity of my 40 amp breaker. I just feel better about it. Have I calculated this correctly??

 

[templdl]

did you take power factor into considerations?
As a rule of thumb if you don't know it a common default is 80% (.80).


Electric Service: 460/3/60 V/Ph/Hz

Compressor Power: 6.17 kW
Fan Power (each): 1.05 kW
Pump Power (each): 0.75 kW
Total kw 7.97 kw

Then there is a second pump**;


Compressor FLA= 10.88 amps
Fan 1 FLA= 1.17 amps
pump 1 = 1.54 amps
Then there is a second pumpump 2 = 2.71 amps

Using a 80pf I assumed that the pf is unknown do you consider pf and that the fans and pumps are in fact 3ph.
To get amperes from kw: I = 1000 ? P / (√3 ? PF ? V ) Your currents seem a bit high.

 

[MidgetD]

I am not sure what the 2.71 amp figure is for. The machine has one pump one compressor and one fan from what I can see. The Nameplate on the pump gives 1.54 amps for a y config and 2.76 amps for delta. The contactor appears to be DOL. In the manufacturers data sheets it lists:

MC1 fla= 10.88 Compressor

MF1 fla= 1.17 Fan motor

MP1 (p3) fla =1.54 this equals amps on nameplate for my voltage

MP1 (p5) fla = 2.71 ????

On the electrical schematic it shows one pump. Out to the side of the overload it shows a table with a different amp setting for P3 anfd P5. I think the 2.71 amps is just if it is wired delta?

 

[templdl]

Since there appears to be a gray area regarding the actual load and your coonsidering a 20a MCCB which may be bit marginal why not just go with a #10 wire with a 30AT breaker and call it a day. It is not that all uncommon for #10 for be used in residential A/C which I used installing mine. Carrier as I recall specified a 20AT breaker for my unit and I was out of them so I stuck in a 2p15at put my clamp-on ampmeter accessory for my Fluke around one of the line when the AC was on and measured 11a and it's been that way for well over ten years.

Just go with the #10 and a 30at breaaker and call it a day. You are spending way to much of your time on this in my opinion.

It may be some of the others will want to jump in on this an beat it up for a while and contribute their opinions but it certainly don't think it's worth what you may be saving going from #12-#10 or from a 20at-30at breaker.

 

[MidgetD]

You are spending way to much of your time on this in my opinion.

I agree!! was gonna go wtih 40 amp breaker because I have one and should be legal with 10 awg. Just wanted to be sure I understood that I was understanding article 440 section II and IV correctly.