WEG CFW900 - 4.3 HELP KEY

English
INSTALLATIONANDCONNECTION
circuits,suchassensors,digitalinputs,loadsondigitaloutputs,etc.viatheVOUToutputofXC1.Inapplications
thatusemultipleaccessories,itmaybenecessarytouseanexternal24Vdcpowersupply.
Followthenextstepstoevaluatetheconsumptionoftheinternalpowersupplyandcalculatethecurrentavailable
inVOUT:
1.Checktheconsumptionoftheaccessoriesthatwillbeinstalledineachbackplaneslotthrough
Table7.2;
2.AddtheconsumptionofeachaccessorytobeconnectedtoslotsAtoGusingtheequation:
I
ACC
= I
ACC,A
+ I
ACC,B
+ I
ACC,C
+ I
ACC,D
+ I
ACC,E
+ I
ACC,F
+ I
ACC,G
,toobtainthetotalconsumption
oftheaccessories;
3.Checkthetotalcurrentconsumedbytheaccessories:
Ifthecurrentdrawnbytheaccessoriesisgreaterthan0.8A,(i.e.,I
ACC
> 0,8A)itwillbenecessarytouse
anexternalpowersupply.Checkitem
3.2.6.2;
Iftheconsumptionoftheaccessoriesislessthanorequalto0.8A(i.e.,I
ACC
≤ 0,8A),theremaining
currentcanbeconsumedthroughtheVOUToutputs.Gotoitem4tocheckthecurrentavailableinVOUT;
4.CalculatethemaximumcurrentinVOUT:I
OU T
= 0,8A− I
ACC
;
5.CheckthatthecircuitstobeconnectedtotheVOUToutputdonotexceedthecalculatedmaximumcurrent
I
OU T
.
Table3.16:ExamplesofhowtochecktheconsumptionoftheinternalpowersupplyandcurrentavailableinVOUT
Ex.
Accessory
(2)
SLOTASLOTBSLOTCSLOTDSLOTESLOTFSLOTGI
ACC
I
OU T
1
Model
REL-01
0.05A0.75A
Consumption
0.05A
2
Model
REL-01TEMP-01CCAN-WENC-01
0.30A0.50A
Consumption
0.05A0.05A0.00A0.20A
3
Model
REL-01TEMP-01CCAN-WENC-01IOAI-01IOD-01IOD-01
0.40A0.40A
Consumption
0.05A0.05A0.00A0.20A0.10A0.00A0.00A
4
Model
REL-01TEMP-01ENC-01ENC-01IOAI-01IOAI-01IOAI-01
0.80A0.00A
Consumption
0.05A0.05A0.20A0.20A0.10A0.10A0.10A
5
(1)
Model
ENC-01ENC-01IOAI-01IOAI-01IOAI-01IOAI-01IOAI-01
0.90A
-0.10A
(1)
Consumption
0.20A0.20A0.10A0.10A0.10A0.10A0.10A
(1)
Inthisexample,thecapacityoftheinternalpowersupplywasexceeded,beingnecessarytouseanexternalpowersupplyas
3.2.6.2.
(2)
Prefix“CFW900”hasbeenomitted.
✓
NOTE!
Ifitisnecessarytouseanexternalpowersupplybecausetheconsumptionofaccessoriesandloads
connectedtoVOUTisgreaterthan0.8A,makesurethattheexternalpowersupplyisenergized
beforeoratthesametimeastheinverter,andthattheinverterisde-energizedbeforeortogether
withtheexternalpowersupply.
3.2.6.2Useofa24VdcExternalPowerSupply
Theexternalpowersupplyoperatesredundantlywiththeinverterinternalpowersupplyandallowsthecontrol,
communicationandaccessorycircuitstoremainactive(poweredandrespondingtocommands)evenwiththe
powercircuitde-energized.
Theinverterindicatesthe“Poff”statewhenthecontrolpowerisactiveandthereisnovoltageontheinverterDC
link.Theuseoftheexternalpowersupplyisalsonecessaryifthetotalcurrentdrawnbytheaccessoriesisgreater
thanthecapacityoftheinverterinternalpowersupply,asexplainedinitem
3.2.6.1.
Whentheexternalpowersupplyisenergized,theinvertercontrolcircuits,accessoriesandloadsconnectedto
theVOUToutputofXC1drawcurrentfromtheexternalpowersupply.ThiswaytheloadsinVOUTwillalsohave
redundantpower.
Followthenextstepstosizetheexternalpowersupply:
CFW900|43