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LRA on faceplate. Is is a Don't Go Over, or is it a This is What It Will Be

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#25 ·
I am curious if it is the second definition or the last? How do we know?

RLA Reverse Logistics Association
RLA Rated Load Amps (electrical engineering)
RLA Residential Landlords Association (UK)
RLA Rod Laver Arena (sports venue; Australia)
RLA Right Livelihood Award (Right Livelihood College; Malaysia)
RLA Registered Landscape Architect
RLA Reading/Language Arts
RLA Repair Line Agreement
RLA Rotate Left Accumulator
RLA Repair Level Analysis
RLA Regional Library Authority
RLA Remote Loop Adapter
RLA Reader License Agreement
RLA Resellers License Agreement
RLA Registrar License and Agreement
RLA Regional Legislative Assembly (Philippines)
RLA Regional and Local Authorities (various locations)
RLA Redevelopment Land Agency
RLA Residential Listing Agreement (real property contract)
RLA Red Light Area
RLA Regional Learning Alliance (Cranberry Township, PA)
RLA Railway Labor Act of 1926 (US)
RLA Real Life Application
RLA Red List Authority (est. 1963; species conservation)
RLA Radio Link Adaptation
RLA Record Level Access
RLA Red Lored Amazon (bird species; Amazona autumnalis)
RLA Remote LAN Access
RLA Residential Living Area (various locations)
RLA Remaining Life Assessment (industrial engineering equipment)
RLA Resident Letting Agents (Australia; real estate training)
RLA Running Line Amperes
RLA Russian Library Association
RLA Repair-Level Analysis
RLA Raymond Loewy Associates (industrial design)
RLA Recreation Liability Act (Nebraska, USA)
RLA Rick Levin & Associates (real estate; Chicago, IL)
RLA Reaction-Limited Aggregation
RLA Robert Land Academy (Canada)
RLA Remote Level Access (AS400 iSeries way of accessing connections)
RLA Royal Liver Assurance (UK)
RLA Regional Lymphadenectomy (surgical procedure)
RLA Responsible Local Agency
RLA Restricted Landing Area (aviation; Illinois)
RLA Ranchos Los Amigos (score measuring the levels of a coma)
RLA Residential Leadership Association
RLA Run Like An Antelope (Phish song)
RLA Resident Life Advisor
RLA Resident Landscape Architect
RLA Register Load Address
RLA Rotary Launch Assembly
RLA Router Link Advertisement
RLA Research Laboratory Assistant
RLA Reverse Link Analysis
RLA Run Load Ampere(s)
 
#26 ·
Because I thought rated load amps were the maximum amps a compressor should draw under any conditions? I think we already determined it would be higher when started than what this plate states it is.
 
#28 ·
FLA is Full Load Amps, max motor rating for continuous operation, as applied rla, can be up to fla.
Normally not listed on compressors.
 
#31 ·
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#32 ·
ehsx said:
FLA is Full Load Amps, max motor rating for continuous operation, as applied rla, can be up to fla.
Normally not listed on compressors.
Click to expand...
FLA is the maximum amps a motor can pull when its maximum hp is reached, not its running load. In other words , I think of running load vs full load like I do when a freezer is pulling down from hot vs holding a temp. Big difference. I think we may be saying the same thing in a different way.
 
#33 ·
Emerson addresses this on their web site. It does affect contactor and starter sizing. A motor with a fla higher than its rla may require a higher rated contactor or starter.
Copeland has an approved contactor list(sb) for the same reason.
 
#34 ·
OnceRude said:
XR17 with no LRA history until

tech #3 : May2021: LRA = 73
tech#3 (2021) wanted to sell me a hard start kit (I declined; he said "it's only going to get worse")


tech #4:May2022: LRA = 81.13 (stage2) (stage1=64.18A)
tech#4 (2022) I request doing all the usual tests in both stage 1 and stage 2

BTW, it never starts in stage 2 as far as I know except setting the XL-824 tstat to test mode, stage 2; it runs in stage 1 (Y1) around 99+% of its run hours overall (only more than a blip in Jul/Aug)


QUESTION 1: Is the compressor getting harder to start - in a bad way?, or

QUESTION 2: Is the measured 81.13 A just about where it should be, according to the (attached image) faceplate?

OAT was 85F. Inside WB was 59.7F.
Click to expand...
I've only checked LRA a few times in my entire career , and it was because the unit was hesitating

If he got higher amps than another guy ... he may have "short cycled" the unit .... which is completely normal to draw more amps when doing that

Seeing the unit has a little 35 amp breaker , it would be tripping if there was an issue
 
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#35 ·
I know NEMA well, learned a lot from them in my systems engineering degree. But I see on the Emerson page you are correct in that RLA does stand for "Rated Load Amps"
on Emerson's page, https://emersonclimate.custhelp.com/app/answers/detail/a_id/5342 ,

Maximum Operating Current (MOC) - Current which serves as a reference in determining the performance of the relay contacts. Used by European Customers. MOC is measured at the top right hand corner of the operating envelope to show the amperage at the highest discharge and suction pressures.
Rated Load Amps (RLA) - Reference current used in contactor and wire selection for US Customers. RLA is calculated from the Maximum Continuous Current (MCC) and serves as a running current value for the compressor. UL uses an RLA value 64% of the MCC (MCC 156% of RLA rating) while Emerson Copeland uses a more conservative RLA value which is 71% of the MCC (MCC 140% of RLA rating) for contactor selection.
Maximum Continuous Current (MCC) - Current measured just prior to protector trip.


So when I read that, I read the definition as: RLA is calculated from the Maximum Continuous Current (MCC) and serves as a running current value for the compressor.

Wait , did that just read that the RLA is the running current value for the compressor? WTH , are we both right? Hmmmmmmmmm
 
#36 ·
Also what lot of techs may not understand is, the voltage to the unit makes a difference in both LRA and FLA. I've personally seen residential voltage here, vary from 215 volts to 245 volts, so sometimes the name place information is worthless.
 
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#38 ·
Can tell you working for chiller mfger’s, rla was determined in the lab at ahri or customer requested design conditions. On design built the motors were frequently oversized to get peak efficiency at a specific load, usually detrimental to light load operations.

No conversion method in this case, request motor fla from engineering dept or motor vendor.
 
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