technical note - analog output

8/13/2019 Technical Note - Analog Output

1/15

TECHNICAL NOTE

Analog Outputs

Introduction .....................................................................................................................2

Analog Output 4-20 mA ..................................................................................................3

Analog Output 0-20 mA ..................................................................................................4

Analog Output 0-1 mA ....................................................................................................5

Analog Output 1 mA......................................................................................................6

Analog Output 0-2 mA range (0-1 mA option with 100% overload) ...............................7

Analog Output 2 mA range (1 mA option with 100% overload)..................................8

Analog Output 0-3 mA range (0-1 mA option with 200% overload) ...............................9

Analog Output 3 mA range (1 mA option with 200% overload)................................10

Analog Output 0-5 mA range (0-1 mA option with 400% overload) .............................11

Analog Output 5 mA range (1 mA option with 400% overload)................................12

Calculation Examples ...................................................................................................13

BB0122 Rev. A2

Copyright 2002-2006 SATEC Ltd.


2/15

2

IntroductionSATEC meters may be equipped with optional analog outputs that are programmable toprovide a current proportional to selected measured electrical parameters.

The devices can be ordered with one of the following analog output options:

0-20 mA 4-20 mA

0-1 mA/0-2 mA 0-1 mA option with 100% overload (regular 0-1 mA order)

1 mA/2 mA - 1 mA option with 100% overload (regular 1 mA order)

0-1 mA/0-3 mA 0-1 mA option with 200% overload (special 0-1 mA order)

1 mA /3 mA - 1 mA option with 200% overload (special 1 mA order)

0-1 mA/0-5 mA 0-1 mA option with 400% overload (special 0-1 mA order)

1 mA /5 mA - 1 mA option with 400% overload (special 1 mA order)

You can find complete setup instructions in the corresponding Installation and OperationManual for your meter. The purpose of this document is to provide guidelines for calculationof analog output currents and corresponding measured (real) parameters.

See the following tables for analog output scales and formulas for calculating analog outputcurrents. The default output scales can be changed via the analog output setup from themeter front panel or through the supplemental PAS software.

Note that the output scales for 0-1 mA and 1 mA analog outputs are always programmedfor 0 mA and +1 mA regardless of the ordered current overload option (100%, 200% or400%). If you wish to use the entire output range of 2 mA, 3 mA or 5 mA, depending on yourorder, set the analog output scales in your device as follows:

0-2 mA: set the 1 mA scale to 1/2 of the required full scale output for uni-directionalparameters, and set the 0 mA scale to the negative full scale and the 1 mA scale to zerofor bi-directional parameters.

2 mA: set the 1 mA scale to 1/2 of the required full-scale output for both uni-directionaland bi-directional parameters.

0-3 mA: set the 1 mA scale to 1/3 of the required full scale output for uni-directionalparameters, and set the 0 mA scale to the negative full scale and the 1 mA scale to 1/3 ofthe negative full scale for bi-directional parameters.

3 mA: set the 1 mA scale to 1/3 of the required full-scale output for both uni-directionaland bi-directional parameters.

0-5 mA: set the 1 mA scale to 1/5 of the required full scale output for uni-directionalparameters, and set the 0 mA scale to the negative full scale and the 1 mA scale to 1/5 ofthe negative full scale for bi-directional parameters.

5 mA: set the 1 mA scale to 1/5 of the required full-scale output for both uni-directional

and bi-directional parameters.


3/15

Analog Output 4-20 mAParameter Programmable scales (Low scale and

High scale), output limits (low andhigh) and typical points, natural units

Analogoutput,mA

Output current calculation,I AO , mA

Real (measured) parameter calcu

Voltage VNo PT

0 V (Low scale, V low)

1.2 690 = 828V (High scale, V high )

4 mA20 mA

Voltagevia PT


144 K, V (High scale, V high )

4 mA20mA

4 V V

16) V V(I

LOWHIGH

LOWREAL AO +

=

16 V V()4I(

VLHIGH AO

REAL

=

Current I 0 A (Low scale, I low)

2 I p, A (High scale, I high )

4 mA20 mA

4II

16)II(ILOWHIGH

LOWREAL AO +

=

16

II()4I(I

LOWHIGH AOREAL

=

Signed powerfactor, PF

-0.0 (Low scale)-0.50-0.991.000.500.0 (High scale)

4 mA8 mA11.88 mA12 mA16 mA20 mA

For negative PF:I AO = 4 - PF REAL 8

For positive PF:I AO = 20 - PF REAL 8

If PF < 12mA:PFREAL=(4-I AO)/8

If PF 12mA:PFREAL= (20 - I AO)/8

Lag and leadpower factor,PF

0.00 (Low scale, PF low)

1.00 (High scale, PF high )

4 mA

20 mA4

PFPF

16)PFPF(I

LOWHIGH

LOWREAL AO +

=

16PF()4I(

PFHIGH AO

REAL

=

Frequency, f 0 Hz (Low scale, f low

)

100 Hz (High scale, f high )

4 mA

20 mA4f f

16)f f (I LOWHIGH

LOWREAL AO +

=

16 f f ()4f (

f LOHIGH AOREAL

=

Active powerkW, P

-(Vhigh Ihigh n), kW (Low scale, P low)

0 kW Vhigh I high n, kW (High scale, P high )

4 mA

12 mA

20 mA

416)(

+

=

PP

PPI

LOWHIGH

LOWREAL AO

16

PP()4I(P

LOWHIGH AOREAL

=

Reactivepower kvar, Q

As for active power 4QQ

16)QQ(I

LOWHIGH

LOWREAL AO +

=

16

QQ()4I(Q LOHIGH AOREAL

=

Apparentpower kVA, S

0 kVA (Low scale, S low)

(Vhigh I high n)/2, kVA

Vhigh I high n, kVA (High scale, S high )

4 mA12 mA20 mA

4SS

16)SS(I

LOWHIGH

LOWREAL AO +

=

16

SS()4I(S LOWHIGH AOREAL

=

Power demand As for apparent power


4/15

4



Analogoutput,mA

Output current calculation,I AO , mA

Real (measured) parametercalculation

Voltage, VNo PT


1.2 690 = 828V (High scale, Vhigh

)

0 mA

20mA

Voltagevia PT



0 mA

20mA

V V20) V V(

ILOWHIGH

LOWREAL AO

=

20 V V(I

V LOWHIGH AOREAL

=

Current, I 0 A (Low scale, I low)

2 Ip, A (High scale, I high )

0 mA

20mA II20)II(

ILOWHIGH

LOWREAL AO

=

20)II(I

I LOWHIGH AOREAL +

=



0 mA5 mA9.9 mA10 mA15 mA20mA

For negative PF:I AO = - PF REAL 10For positive PF:I AO = 20 -PF REAL 10

If PF < 10 mA:PFREAL= -I AO /10

If PF 10 mA:PFREAL= (20 - I AO)/10

Lag and leadpower factor, PF



0 mA

20mA PFPF20)PFPF(

ILOWHIGH

LOWREAL AO

=

20

PFPF(IPF LOHIGH AOREAL

=

Frequency, f 0 Hz (Low scale, f low)100 Hz (High scale, f high )

0 mA20mA f f

20)f f

(I

LOWHIGHLOWREAL AO

=

20

)f f

(f f LOWHIGH AOREAL +

=

Active power, kW,P



0 mA

10 mA

20 mA

PP20)PP(

ILOWHIGH

LOWREAL AO

=

20

)PP(IP LOWHIGH AOREAL +

=

Reactive powerkvar, Q

As for active powerQQ

20)QQ(I

LOWHIGH

LOWREAL AO

=

20

)QQ(IQ LOWHIGH AOREAL +

=

Apparent powerkVA, S




0 mA

10 mA

20 mA

SS20)SS(

ILOWHIGH

LOWREAL AO

=

20SS(I

S LOWHIGH AOREAL

=



5/15



Analogoutput,mA

Output currentcalculation, I AO , mA


Voltage, V

No PT


1.2 690 = 828V (High scale, V high )

0 mA

1 mA Voltage, Vvia PT



0 mA

1 mA

V V

V VI

LOWHIGH

LOWREAL AO

=

VREAL= I AO

(VHIGH - VLOW) + V LOW

Current, I 0 A (Low scale, I low)


0 mA

1 mA IIIIILOWHIGH

LOWREAL AO

=

IREAL= I AO (I HIGH - I LOW) + I LOW



0 mA0.25 mA0.495 mA0.5 mA0.75 mA1 mA

For negative PF:I AO = - PF REAL 0.5For positive PF:I AO = 1 - PF REAL 0.5

If PF < 0.5 mA:PFREAL = -I AO 2

If PF 0.5 mA:PFREAL= (1- I AO) 2




0 mA

1 mA PFPFPFPF

ILOWHIGH

LOWREAL AO

=

PFREAL= I AO (PF HIGH - PFLOW) + PF

Frequency, f 0 Hz (Low scale, f low)100 Hz (High scale, f high )

0 mA1 mA f f

f f ILOWHIGH

LOWREAL AO

= f REAL= I AO (f HIGH - f LOW) + f LOW

Active power, kW,P



0 mA

0.5 mA

1 mA

PPPP

ILOWHIGH

LOWREAL AO

= PREAL= I AO (P HIGH - P LOW) + P LOW


As for active powerQQQQ

ILOWHIGH

LOWREAL AO

=

QREAL= I AO (Q HIGH - QLOW) + Q LOW





0 mA

0.5 mA

1 mA

SSSS

ILOWHIGH

LOWREAL AO

= SREAL= I AO (S HIGH - S LOW) + S LOW



6/15

6

Analog Output 1 mAParameter Programmable scales (Low scale and


Analogoutput, mA



Voltage, VNo PT


1.2 690 = 828V (High scale, Vhigh

)

0 mA

1 mA

Voltage, Vvia PT



0 mA

1 mA

V V V V

ILOWHIGH

LOWREAL AO

=

VREAL= I AO (VHIGH - VLOW) +



0 mA

1 mA IIII

ILOWHIGH

LOWREAL AO

=

IREAL= I AO (I HIGH - I LOW) + I


-0.0-0.50-0.991.00 (Low scale)0.500.0 (High scale)

-1 mA-0.5 mA-0.01 mA0 mA0.5 mA1 mA

For negative PF:I AO = -1 - PF REAL For positive PF:I AO = 1 - PF REAL

If PF < 0 mA:PFREAL= -1 - I AO

If PF 0 mA:PFREAL= 1- I AO




0 mA1 mA PFPF

PFPFI

LOWHIGH

LOWREAL AO

= PFREAL= I AO (PF HIGH - PFLO

Frequency, f 0 Hz (Low scale, f low

)

100 Hz (High scale, f high )

0 mA1 mA f f

f f I

LOWHIGH

LOWREAL AO

= f REAL= I AO (f HIGH - f LOW) + f

Active power,kWP

-(Vhigh Ihigh n), kW (P low)

0 kW (Low scale) Vhigh I high n, kW (High scale, P high )

-1 mA

0 mA

1 mA

1PP

2)PP(I

LOWHIGH

LOWREAL AO

= PREAL= (I AO + 1) (P HIGH - P


As for active power1

QQ

2)QQ(I

LOWHIGH

LOWREAL AO

=

QREAL= (I AO + 1) (Q HIGH - Q





0 mA

0.5 mA

1 mA

SSSS

ILOWHIGH

LOWREAL AO

= SREAL= I AO (S HIGH - S LOW) +

Accumulatedpower demands

As for apparent power


7/15

Analog Output 0-2 mA range (0-1 mA option with 100% overload)Parameter Programmable scales (Low scale and


Analogoutput,mA



Voltage, VNo PT


(1.2

690)/2 = 414V (High scale)1.2 690 = 828V (V high )

0 mA

1 mA2 mA

Voltage, Vvia PT


(144 K)/2, V (High scale)144 K, V (Vhigh )

0 mA

1 mA

2 mA

V V

2) V V(I

LOWHIGH

LOWREAL AO

=

V

2) V V(I V L

LOWHIGH AOREAL +

=


(2 I p)/2, A (High scale)

2 Ip, A (I high )

0 mA

1 mA

2 mA

II

2)II(I

LOWHIGH

LOWREAL AO

=

I

2

)II(II LOWHIGH AOREAL +

=


-0.0 (Low scale)-0.501.00 (High scale)0.500.0

0 mA0.5 mA1 mA1.5 mA2 mA

For negative PF:I AO = - PF REAL For positive PF:I AO = 2 - PF REAL

If PF< 1.0 mA:PFREAL= -I AO

If PF 1.0 mA:PFREAL= 2 - I AO


0.00 (Low scale, PF low)0.50 (High scale)1.00 (PF high )

0 mA1 mA

2 mA

PFPF2)PFPF(I

LOWHIGHLOWREAL AO

= 2

)PFPF(IPF LOWHIGH AOREAL +=

Frequency, f 0 Hz (Low scale, f low)

50 Hz (High scale)100 Hz (f high )

0 mA

1 mA

2 mA

f f

2)f f (I

LOWHIGH

LOWREAL AO

=

f

2

)f f (f f L

LOWHIGH AOREAL +

=

Active powerkW, P


0 kW (High scale) Vhigh I high n, kW (P high )

0 mA

1 mA

2 mA

PP

2)PP(I

LOWHIGH

LOWREAL AO

=

P

2

)PP(IP LOWHIGH AOREAL +

=



2)QQ(I

LOWHIGH

LOWREAL AO

=

Q

2

)QQ(IQ LOWHIGH AOREAL +

=

Apparent power

kVA, S


(Vhigh I high n)/2, kVA, (High scale) Vhigh I high n, kVA (S high )

0 mA

1 mA2 mA

SS

2)SS(I

LOWHIGH

LOWREAL AO

=

S

2

)SS(IS L

LOWHIGH AOREAL +

=


For using the entire output range of 2 mA, set the 1 mA scale in your device to 1/2 of the required full scale output for uni-directional parameters, and set the 0full scale and the 1 mA scale to zero for bi-directional parameters.


8/15

8

Analog Output 2 mA range (1 mA option with 100% overload)Parameter Programmable scales (Low scale and


Analogoutput,mA



Voltage, VNo PT


(1.2 690)/2 = 414V (High scale)

1.2 690 = 828V (V high )

0 mA

1 mA

2 mA

Voltagevia PT



0 mA

1 mA

2 mA

V V

2) V V(I

LOWHIGH

LOWREAL AO

=

V

2) V V(I V L

LOWHIGH AOREAL +

=



2 I p, A (I high )

0 mA

1 mA

2 mA

II

2)II(I

LOWHIGH

LOWREAL AO

=

2


=


-0.0-0.501.00 (Low scale)0.50 (High scale)0.0

-2 mA-1 mA0 mA1 mA2 mA

For negative PF:I AO = -2 (1 + PF REAL)For positive PF:I AO = 2 (1 - PF REAL)

If PF < 0 mA:PFREAL= -1 - I AO /2

If PF 0 mA:PFREAL= 1 - I AO /2

Lag and leadpower factor, PF 0.00 (Low scale, PF low)0.50 (High scale)1.00 (PF high )

0 mA1 mA

2 mA

PFPF2)PFPF(I

LOWHIGHLOWREAL AO

=

2)PFPF(IPF LOWHIGH AOREAL +=



0 mA

1 mA

2 mA

f f

2)f f (I

LOWHIGH

LOWREAL AO

=

f

2

)f f (f f L

LOWHIGH AOREAL +

=

Active power,kW, P


0 kW, (Low scale)(Vhigh I high n)/2, kW (High scale)

Vhigh I high n, kW (P high )

-2 mA

0 mA

1 mA

2 mA

2PP

4)PP(I

LOWHIGH

LOWREAL AO

= PREAL= (I AO + 2) (P HIGH - P LOW)



QQ

4)QQ(I

LOWHIGH

LOWREAL AO

=

QREAL= (I AO + 2) (Q HIGH - Q LOW

Apparent powerkVA, S 0 kVA (Low scale, S low)(Vhigh I high n)/2, kVA, (High scale)

Vhigh I high n, kVA (S high )

0 mA1 mA

2 mA

SS

2)SS

(I

LOWHIGHLOWREAL AO

=

S

2

)SS

(IS LOWHIGH AOREAL +

=


For using the entire output range of 2 mA, set the 1 mA scale in your device to 1/2 of the required full scale output for both uni-directional and bi-directional


9/15



Analogoutput,mA



Voltage, VNo PT


(1.2

690)/3 = 414V (High scale)1.2 690 = 828V (V high )

0 mA

1 mA3 mA

Voltage, Vvia PT



0 mA

1 mA

3 mA

V V

3) V V(I

LOWHIGH

LOWREAL AO

=

V

3) V V(I V LOWHIGH AOREAL +

=



2 Ip, A (I high )

0 mA

1 mA

3 mA

II

3)II(I

LOWHIGH

LOWREAL AO

=

I3


=


-0.0 (Low scale)-0.50-0.667 (High scale)1.000.50

0.0

0 mA0.75 mA1 mA1.5 mA2.25 mA

3 mA

For negative PF:I AO = -PF REAL 3/2For positive PF:I AO = 3 - PF REAL 3/2

If PF< 1.5 mA:PFREAL= -I AO 2/3

If PF 1.5 mA:PFREAL= (3 - I AO) 2/3



0.333 (High scale)1.00 (PF high )

0 mA

1 mA

3 mA

PFPF

3)PFPF(I

LOWHIGH

LOWREAL AO

=

3

)PFPF(IPF LOWHIGH AOREAL +

=



0 mA

1 mA

3 mA

f f

3)f f (I

LOWHIGH

LOWREAL AO

=

f

3)f f (f

f LOLOWHIGH AO

REAL +

=

Active powerkW, P


-(Vhigh I high n)/3, kW (High scale)

0 kW Vhigh I high n, kW (P high )

0 mA

1 mA

1.5 mA

3 mA

PP

3)PP(I

LOWHIGH

LOWREAL AO

=

P

3)PP(I

P LOWHIGH AOREAL +

=



3)QQ(I

LOWHIGH

LOWREAL AO

= Q

3)QQ(I

Q LOWHIGH AOREAL +

=



(Vhigh I high n)/3, kVA, (High scale)


0 mA

1 mA

3 mA

SS

3)SS(I

LOWHIGH

LOWREAL AO

=

S

3)SS(I

S LLOWHIGH AO

REAL +

=


For using the entire output range of 3 mA, set the 1 mA scale in your device to 1/3 of the required full scale output for uni-directional parameters, and set the 0full scale and the 1 mA scale to 1/3 of the negative full scale for bi-directional parameters.


10/15

10



Analogoutput,mA



Voltage, VNo PT


(1.2 690)/3 = 414V (High scale)

1.2 690 = 828V (V high )

0 mA

1 mA

3 mA

Voltagevia PT

0V (Low scale, V low)


0 mA

1 mA

3 mA

V V

3) V V(I

LOWHIGH

LOWREAL AO

=

V

3) V V(I V LOWHIGH AOREAL +

=


(2 Ip)/3, A (High scale)

2 I p, A (I high )

0 mA

1 mA

3 mA

II

3)II(I

LOWHIGH

LOWREAL AO

=

3


=








0 mA1 mA

3 mA

PFPF3)PFPF(I

LOWHIGHLOWREAL AO

= 3 )PFPF(IPF

LOWHIGH AOREAL +=



0 mA

1 mA

3 mA

f f

3)f f (I

LOWHIGH

LOWREAL AO

=

f

3)f f (f

f LLOWHIGH AO

REAL +

=

Active power,kW, P




-3 mA

0 mA

1 mA

3 mA

3PP

6)PP(I

LOWHIGH

LOWREAL AO

= PREAL= (I AO + 3) (P HIGH - P LOW)



QQ

6)QQ(I

LOWHIGH

LOWREAL AO

=

QREAL= (I AO + 3) (Q HIGH - QLOW

Apparent powerkVA, S 0 kVA (Low scale, S low)(Vhigh I high n)/3, kVA, (High scale)


0 mA1 mA

3 mA

SS

3)SS

(I

LOWHIGHLOWREAL AO

=

S3

)SS

(IS LOWHIGH AOREAL +

=




11/15



Analogoutput,mA



Voltage, VNo PT


(1.2

690)/5 = 165.6V (High scale)1.2 690 = 828V (V high )

0 mA

1 mA5 mA

Voltage, Vvia PT



0 mA

1 mA

5 mA

VVVV

ILOWHIGH

LOWREAL AO

)(

=

5 V

VVIV L

LOWHIGH AOREAL

)(+

=

5



2 Ip, A (I high )

0 mA

1 mA

5 mA

IIII

ILOWHIGH

LOWREAL AO

)(

=

5 I

IIII LOW

LOWHIGH AOREAL

)(+

=

5


-0.0 (Low scale)-0.4 (High scale)-0.501.000.50

0.0

0 mA1 mA1.25 mA2.5 mA3.75 mA

5 mA

For negative PF:I AO = -PF REAL 5/2For positive PF:I AO = 5 - PF REAL 5/2

If PF< 2.5 mA:PFREAL= -I AO 2/5

If PF 2.5 mA:PFREAL= (5 - I AO) 2/5



0.200 (High scale)1.00 (PF high )

0 mA

1 mA

5 mA

PFPFPFPF

ILOWHIGH

LOWREAL AO

)(

=

5 PFPFIPF

LOWHIGH AOREAL

)(+

=

5



0 mA

1 mA

5 mA

f f f f

ILOWHIGH

LOWREAL AO

)(

=

5 f

f f f f LOW

LOWHIGH AOREAL

)(+

=

5

Active powerkW, P


-(Vhigh I high n)/5, kW (High scale)

0 kW Vhigh I high n, kW (P high )

0 mA

1 mA

2.5 mA

5 mA

PPPP

ILOWHIGH

LOWREAL AO

)(

=

5 P

PPIP L

LOWHIGH AOREAL

)(+

=

5



QQI

LOWHIGH

LOWREAL AO

)(

=

5 Q

QQIQ

LOWHIGH AOREAL

)(+

=

5





0 mA

1 mA

5 mA

SSSS

ILOWHIGH

LOWREAL AO

)(

=

5 S

SSIS L

LOWHIGH AOREAL

)(+

=

5


For using the entire output range of 5 mA, set the 1 mA scale in your device to 1/5 of the required full scale output for uni-directional parameters, and set the 0full scale and the 1 mA scale to 1/5 of the negative full scale for bi-directional parameters.


12/15

12



Analogoutput,mA



Voltage, VNo PT


(1.2 690)/5 = 165.6V (High scale)

1.2 690 = 828V (V high )

0 mA

1 mA

5 mA

Voltagevia PT

0V (Low scale, V low)


0 mA

1 mA

5 mA

VVVV

ILOWHIGH

LOWREAL AO

)(

=

5 V

VVIV

LOWHIGH AOREAL

)(+

=

5


(2 Ip)/5, A (High scale)

2 I p, A (I high )

0 mA

1 mA

5 mA

IIII

ILOWHIGH

LOWREAL AO

)(

=

5 I

IIII LO

LOWHIGH AOREAL

)(+

=

5








0 mA1 mA

5 mA

PFPFPFPFI

LOWHIGHLOWREAL AO )(

= 5 PFPFIPF LOWHIGH AOREAL )( +

=

5



0 mA

1 mA

5 mA

f f f f

ILOWHIGH

LOWREAL AO

)(

=

5 f

f f f f LO

LOWHIGH AOREAL

)(+

=

5

Active power,kW, P




-5 mA

0 mA

1 mA

5 mA

510

=

PPPP

ILOWHIGH

LOWREAL AO

)( PREAL= (I AO + 5) (P HIGH - P LOW)


As for active power 510

=

QQQQ

ILOWHIGH

LOWREAL AO

)( QREAL= (I AO + 5) (Q HIGH - QLOWQLOW


0 kVA (Low scale, Slow

)



0 mA

1 mA

5 mA

SSSS

I LOWHIGHLOWREAL

AO

)(

=

5 S

SSIS

LOWHIGH AOREAL

)(+

= 5




13/15

13

Calculation Examples

Example 1

The meter is installed on a 24 kV power line with 400:5A current transformers and24,000:120V potential transformers:

Ip = CT primary current = 400A and 3-phase

K = PT ratio = 24000/120 = 200.

Wiring configuration is 4Ln3, n = 3.

The full-scale analog output ranges are as fol lows:

Voltage:

Low voltage V low = 0 V.

High voltage V high = 144 K=144 200 = 28800 V.

Current:

Low current I low (0 or 4 mA) = 0 A,

High current I high = 2 Ip = 2 400 = 800 A

Active and reactive power:

Low power P low = - n Vhigh Ihigh /1000 = -3 28800 800/1000 = -69,120 kW (kvar)

High power P high = n Vhigh Ihigh /1000 = 3 28800 800/1000 = 69,120 kW (kvar)

The programmable analog output scales should be as follow s:

Voltage:

Low scale, 0 mA/4 mA (all ranges): 0 V.

High scale, 1 mA/20 mA (4-20 mA, 0-20 mA, 0-1mA, 1 mA ranges): V high = 28800 V.

High scale, 1 mA (0-2 mA, 2 mA ranges): V high /2 = 28800/2 = 14400 V.

High scale, 1 mA (0-3 mA, 3 mA ranges): V high /3 = 28800/2 = 9600 V.

Current:

Low scale, 0 mA/4 mA (all ranges): 0 A.

High scale, 1 mA/20 mA (4-20 mA, 0-20 mA, 0-1mA, 1 mA ranges): I high = 800 A.

High scale, 1 mA (0-2 mA, 2 mA ranges): I high /2 = 800/2 = 400 A.

High scale, 1 mA (0-3 mA, 3 mA ranges): I high /3 = 800/3 = 267 A.

Active and reactive power:

Low scale, 0 mA/4 mA (4-20 mA, 0-20 mA, 0-1 mA, 0-2 mA, 0-3 mA ranges): P low =-69,120 kW (kvar).

Low scale, 0 mA (1 mA, 2 mA, 3 mA range): P low = 0 kW (kvar).

High scale, 1 mA/20 mA (4-20 mA, 0-20 mA, 0-1mA, 1 mA ranges): P high = 69,120 kW(kvar).High scale, 1 mA (0-2 mA range): 0 kW (kvar).

High scale, 1 mA (2 mA range): P high /2 = 69,120/2 = 34560 kW (kvar).

High scale, 1 mA (0-3 mA range): P low /3 = -69,120/3 = -11520 kW (kvar).

High scale, 1 mA (3 mA range): P high /3 = 69,120/3 = 11520 kW (kvar).


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Example 2

The meter with regular 1 mA analog outputs (100% overload) is installed on the power lineof Example 1. The analog outputs are programmed in the meter for the 1 mA output range.

What should the analog output currents be if the instrument shows the following measuredreal) quantities?

Voltage = 24,800 VCurrent = 460A Active power P TOTAL = 17170 kW Apparent power S TOTAL = 19736 kVA

The output curr ents would be as follow s:

Voltage output: 0.861mA028800024800

VVVV

ILOWHIGH

LOWREAL AO =

=

=

Current output: mA 575.008000460

IIII

ILOWHIGH

LOWREAL AO =

=

=

Active power output: mA 248.01)69120(69120

2))69120(17170((1

PP

2)PP(I

LOWHIGH

LOWREAL AO =

=

=

Apparent power output: mA 286.0069120019736

SSSS

ILOWHIGH

LOWREAL AO =

=

=

Example 3

The meter with regular 1 mA analog outputs (100% overload) is installed on the power lineof Example 1. The analog outputs are programmed in the meter for the 2 mA output range.

What should the analog output currents be if the instrument shows the measured real)quantities like in Example 2?

The output curr ents would be as follow s:

Voltage output: mA.722028800

20)(24800

VV

V(VI

LOWHIGH

LOWREAL AO 1

2)=

=

=

Current output: mA 15.10800

2)0460(

II

II(I

LOWHIGH

2)LOWREAL AO =

=

=

Active power output: mA 497.02)69120(69120

4))69120(17170((2

PP

4)PP(I

LOWHIGH

LOWREAL AO =

=

=

Apparent power output: mA 571.00691202)019736(

SS

SS(I

LOWHIGH

2)LOWREAL AO =

=

=

Example 4The meter with regular 1 mA analog outputs (100% overload) is installed on the power lineof Example 1. The analog outputs are programmed in the meter for the 2 mA output range.

Which real electrical quantities does the meter measure if the analog output currents are asfollows?

Voltage analog output I AO1 = 0.861 mA

Current analog output I AO2 = 1.15 mA

Active power analog output I AO3 = 0.497 mA


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Apparent power analog output I AO4 = 0.571 mA

The meter readings w ould be as follows:

Measured voltage: V REAL = I AO (VHIGH - VLOW )/2 + V LOW = 0.861 (28800 - 0)/2 + 0= 12398 V

Measured current: I REAL = I AO (IHIGH - ILOW )/2 + I LOW = 1.15 (800 - 0)/2 + 0 = 460 A

Measured active power: P REAL = (I AO + 2) (P HIGH - P LOW )/4 + P LOW = (0.497 + 2) (69120 (-69120))/4 + (-69120) =17176 kW

Measured apparent power: S REAL = I AO (S HIGH - S LOW )/2 + S LOW = 0.571 (69120 - 0)/2 + 0 =19734 kVA

technical note - analog output

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