Stabilized differential relay SPAD 346 C

1MRS 750398-MBG
Page 1
Issued: April 1999
Status: New
Data subject to change without notice

Features • Integrated three-phase differential relay, • Second harmonic restraint for prevention of
three-phase overcurrent relay and multi- unwanted relay operations at transformer
configurable earth-fault relay inrush currents
• Alarm channels activated by normally open • Fifth harmonic restraint for prevention of
or normally closed contact unwanted relay operations at transformer
overexcitation. The fifth harmonic restraint
• Stabilized differential relay module provid-
can be aborted if the ratio of the fifth har-
ing winding short-circuit and interturn fault
monic and the basic frequency component
protection for two-winding power trans-
rises too high at dangerous overvoltages
formers and generator-transformer units,
and interwinding short-circuit protection for • Wide CT ratio correction range: accurate
generators correction through digital setting
• Earth-fault relay module providing protec- • No interposing current transformers
tion for transformer HV and LV side accord- needed for the protection of two-winding
ing to the principle selected: stabilized power transformers: numerical vector
differential current principle, high-imped- group matching on HV and LV side
ance principle, residual current principle or
• Four heavy-duty output relays for circuit
neutral current principle
breaker tripping and five output relays for
• Three-stage overcurrent module providing signalling
protection for power transformers and gen-
• Five programmable external control inputs
erators and two-stage back-up earth-fault
intended for alarm and trip signals from gas
protection
relays, oil temperature sensors and other
• Short operate time even at partial satura- sensors of transformer auxiliary devices
tion of the current transformers
• Integrated circuit-breaker failure protection
• Operation characteristic of differential relay with adjustable operate time
module easily adapted for different applica-
• Differential relay and earth-fault relay mod-
tions
ules provided with integrated disturbance
• Stabilized against unwanted operations at recorder functions for analog and digital
faults occurring outside the protected area signals: signals to be used for triggering
and at transformer inrush currents selectable
ABB Network Partner Stabilized differential relay SPAD 346 C
1MRS 750398-MBG
Page 2

• Sensitive phase current and phase angle • Powerful software supports relay parame-
displays facilitate checking of energizing terization and reading of measured and
circuit connections and vector group recorded values and event data
matchings
• Member of the SPACOM product family,
• High immunity to electrical and electromag- ABB’s Distribution Automation system and
netic interference allows the relay to be ABB’s Panorama concept
used in severe environments
• CE marking according to the EC directive
• High availability and system reliability due for EMC
to continuous supervision of hardware and
software

Application The stabilized differential relay SPAD 346 C is supplied from the same direction, and for
is designed for protecting two-winding power the protection of compensating chokes and
transformers and generator-transformer units short cable lines.
against winding short-circuit, interturn fault,
earth fault and short circuit, and generators No interposing transformers are needed for
and motors against interwinding faults and the protection of two-winding power trans-
pole short circuit. In addition, the relay can be formers, as the relay allows the vector group
used for the protection of three-winding matching, the elimination of the zero-
power transformers, provided 75% of the sequence component of the phase currents
short circuit power to the power transformer and the CT ratio corrections to be carried out
numerically.

Design The feeder protection relay is provided with The instantaneous, non-stabilized differential
six energizing inputs for phase currents and current unit functions as an ultra-fast protec-
inputs for residual or neutral currents. The tion unit with an operate time less than 30 ms
relay is also equipped with nine output relays at heavy faults.
for CB control, signalling, etc.
The circuit-breaker failure protection unit is
The differential relay consists of three protec- activated by the main trip signal of the other
tion relay modules, i.e. a differential relay protection units and it provides a second trip
module, an earth-fault relay module and a signal to be routed to a back-up circuit
combined overcurrent and earth-fault relay breaker if the main CB fails to operate.
module. The modules are withdrawable as are
the power supply module and the I/O relay The differential relay module also incorpo-
module located behind the system front rates a digital disturbance recorder module.
panel. The module continuously monitors the object
protected and stores pre- and post-fault net-
work information, which can be used for
Differential relay module post-fault analysis.
SPCS 3D53
The differential relay module includes three
protection units, i.e. a stabilized differential Earth-fault relay module
current unit, an instantaneous differential cur- SPCD 2D55
rent unit and a circuit-breaker failure protec- The earth-fault relay module measures the
tion unit. In addition, the module contains a neutral current and/or residual current on both
disturbance recorder unit. sides of the object protected. The earth-fault
protection can be implemented by four differ-
The stabilized differential current unit consti- ent principles, i.e. the high-impedance princi-
tutes the main differential protection. The ple, the numerical stabilized differential
unit is provided with second and third har- current principle, the residual overcurrent
monic restraint, selectable transformer vector principle or the neutral overcurrent principle.
group, zero-sequence current elimination, Both sides of the object can be protected
numerical correction of CT ratios and flexible independent of each other, which means that
configuration of tripping, blocking and con- the protection principle on one side does not
trol signals. have to be the same as that of the other side.
ABB Network Partner Stabilized differential relay SPAD 346 C
1MRS 750398-MBG
Page 3

The circuit-breaker failure protection unit is Data communication

activated by the main trip signal of the pro- The feeder protection relay is equipped with a
tection units and it provides a second trip sig- serial communication port on the rear panel.
nal to be routed to a back-up circuit breaker if The serial port is used for connecting the
the main CB fails to operate. relay to the SPA bus via an optional bus con-
nection module. Two bus connection module
The earth-fault relay module also incorpo- types are available: SPA-ZC 17 and SPA-
rates a digital disturbance recorder module. ZC 21. The former can be powered from the
The module continuously monitors the object host relay and from a separate power source
protected and stores pre- and post-fault net- at the same time, while the latter is powered
work information, which can be used for from the host relay via the D-type connector.
post-fault analysis.
Output relays and circuit
Combined overcurrent and breaker control
earth-fault relay module The feeder protection relay is provided with
SPCJ 2D28 nine output auxiliary relays, four of which are
The combined overcurrent and earth-fault heavy-duty output relays for the direct control
module includes four protection units, i.e. an of the circuit breaker. Single-pole or double-
overcurrent unit, an earth-fault unit, a phase pole circuit breaker control can be used. One
discontinuity unit and a circuit-breaker failure of the five signalling relays is permanently
protection unit. allocated for the self-supervision system. The
function of the other four relays can be
The three-phase overcurrent unit comprises defined by the user.
three overcurrent stages, i.e. a low-set stage
I>, a high-set stage I>> and a super high-set
stage I>>>. The low-set stage can be given
Self-supervision
definite time characteristic or inverse time The relay incorporates a sophisticated self-
supervision system with auto-diagnosis,
characteristic while the high-set stage and the
which increases the availability of the relay
super high-set stage have a definite time char-
acteristic. and the reliability of the system. The self-
supervision system continuously monitors the
hardware and the software of the relay. The
The non-directional earth-fault unit com-
prises two protection stages, i.e. a low-set system also supervises the operation of the
auxiliary supply module and the voltages
stage I0> and a high-set stage I0>>. The low-
generated by the module.
set stage can be given definite time character-
istic or inverse time characteristic while the
high-set stage has a definite time characteris- Auxiliary supply voltage
tic. The auxiliary supply of the relay is obtained
from an internal plug-in type power supply
The phase discontinuity protection unit mea- module. Two auxiliary power module ver-
sures the phase unbalance and has a definite sions are available: type SPGU 240A1 for the
time characteristic. supply voltage range 80…265 V ac/dc and
type SPGU 48B2 for the supply voltage range
The circuit-breaker failure protection unit is 18…80 V dc. The power supply module
activated by the main trip signal of the pro- forms the internal voltages required by the
tection units and it provides a second trip sig- protection relay and the I/O module.
nal to be routed to a back-up circuit breaker if
the main CB fails to operate.
ABB Network Partner Stabilized differential relay SPAD 346 C
1MRS 750398-MBG
Page 4

Technical data Table 1: Energizing inputs

Terminals X0/1-3, 4-6, 7-9, X0/1-2, 4-5, 7-8,
X0/13-15, 16-18, X0/13-14, 16-17,
X0/19-21, 25-27 X0/19-20, 25-26,
X0/37-39 X0/37-38
Rated current In 1A 5A
Thermal current continuously 4A 20 A
withstand for 10 s 25 A 100 A
for 1 s 100 A 500 A
Dynamic current Half-wave value 250 A 1250 A
withstand
Input impedance <100 mΩ <20 mΩ
Rated frequency fn, according to order 50 Hz or 60 Hz

Table 2: Output contact ratings

Type of contact Tripping Signalling
Terminals X1/11-12-13-14 X2/7-8, 9-10
X1/15-16-17-18 X2/11-12-13
X2/3-4, 5-6 X2/14-15
X2/16-17-18
Rated voltage 250 V ac/dc
Thermal withstand Carry continuously 5A 5A
capability Make and carry for 0.5 s 30 A 10 A
Make and carry for 3 s 15 A 8A
Breaking capacity for dc, 220 V dc 1A 0.15 A
when the signal circuit 110 V dc 3A 0.25 A
time constant
48 V dc 5A 1A
L/R ≤ 40 ms, at the
signalling voltage levels
Contact material AgCdO2

Table 3: External control inputs

Terminals X1/1-2, 3-4, 5-6, 7-8,
9-10
Control voltage Operative range 18…265 V dc or
80…265 V ac
Current drain of activated control input 2…20 mA
Active state of input Input active when energized
Input active when non-energized

Table 4: Auxiliary supply modules

Terminal numbers X2/1-2
Type of module Rated voltages Un SPGU 240A1 110/120/230/240 V ac
110/125/220 V dc
SPGU 48B2 24/48/60 V ac
Operative range SPGU 240A1 80…265 V ac/dc
SPGU 48B2 18…80 V dc
Power consumption under quiescent ~10 W
conditions
under operating ~15 W
conditions
ABB Network Partner Stabilized differential relay SPAD 346 C
1MRS 750398-MBG
Page 5

Table 5: Stabilized differential relay module SPCD 3D53

Selectable rated frequency fn 16 2/3…60 Hz
CT ratio correction range on power transformer HV side I1/In 0.40…1.50
CT ratio correction range on power transformer LV side I2/In 0.40…1.50
Stabilized differential current stage 3∆I>
Basic start ratio P/In 5…50%
Starting ratio setting S 10…50%
Second turning point I2tp/In of characteristic curve 1.0…3.0
Harmonics blocking ratio Id2f/Id1f 7…20%
Harmonics blocking ratio Id5f/Id1f 10…50%
Harmonics deblocking ratio Id5f/Id1f 10…50%
Operate time (including heavy-duty output relays at currents 1.5…4 × <50 ms
operate value
at currents above 4 × <45 ms
operate value
Operation accuracy ±4% of set value or
±2% × In
Instantaneous differential current stage 3∆I>>
Start ratio Id/In>> 5…30
Operate time (including heavy-duty output relays at ratios in the range of <35 ms
1.1…2.6 × Id/In>>
at ratios above 2.6 × <30 ms
Id/In>>
Operation accuracy ±4% of set value of 2% ×
In
Circuit-breaker failure protection
Operate time 0.1…1.0 s
Integrated disturbance recorder
Recording length 38 cycles
Recording memory capacity 1 recording = 38 cycles
Sampling frequency 40 samples/cycle
Signals to be recorded 6 analog signals
11 digital signals
Triggering when the selected digital is activated
signal
when the selected digital resets
signal
Length of recording preceding triggering 0…38 cycles

Table 6: Earth-fault relay module SPCD 2D55

Selectable rated frequency fn 16 2/3…60 Hz
Stabilized differential relay principle
Basic start ratio on HV side P1/In 5…50%
Operate time on HV side t01> 0.03…100 s
Basic start ratio on LV side P2/In 5…50%
Operate time setting on LV side t02> 0.03…100 s
Correction range of HV side neutral connection CT ratio I01/In 0.40…1.50
Setting of minimum ratio of HV side neutral current and residual current of 0…20%
phase currents I01/∑I1
Correction range of LV side neutral connection CT ratio I02/In 0.40…1.50
Setting of minimum ratio of LV side neutral current and residual current of 0…20%
phase currents I02/∑I2
Second harmonics restraint ratio I2f/I1f of HV side neutral current I01 10…50%
Second harmonics restraint ratio I2f/I1f of LV side neutral current I02 10…50%
Correction range of HV side phase CT ratio I1/In 0.40…1.50
Correction range of HV side phase CT ratio I2/In 0.40…1.50
ABB Network Partner Stabilized differential relay SPAD 346 C
1MRS 750398-MBG
Page 6

Technical data (cont’d) Table 6: Earth-fault relay module SPCD 2D55

Operate time at minimum delay (including heavy-duty output relays) 30…40 ms
Operation accuracy ±4% of set value or
±2% of In
Principle based on calculated residual current
Basic start ratio P 1/In on HV side 5…50%
Operate time t01> on HV side 0.03…100 s
Basic start ratio P 2/In on LV side 5…50%
Operate time setting t02> on LV side 0.03…100 s
Correction range of HV side phase CT ratio I1/In 0.40…1.50
Correction range of HV side phase CT ratio I2/In 0.40…1.50
Operate time at minimum delay (including heavy-duty output relays) 30…40 ms
Operation accuracy ±4% of set value or
±2% of In
Principle based on measured residual current or neutral current
Basic start ratio P 1/In on HV side 5…50%
Operate time t01> on HV side 0.03…100 s
Basic start ratio P 2/In on LV side 5…50%
Operate time setting t02> on LV side 0.03…100 s
Correction range of HV side neutral connection CT ratio I01/In 0.40…1.50
Correction range of LV side neutral connection CT ratio I02/In 0.40…1.50
Second harmonics restraint ratio I2f/I1f of HV side neutral current I01 10…50%
Second harmonics restraint ratio I2f/I1f of LV side neutral current I02 10…50%
Operate time at minimum delay (including heavy-duty output relays) 30…40 ms
Operation accuracy ±4% of set value or
±2% of In
Restricted earth-fault principle (high-impedance type earth-fault protection)
Basic start ratio P 1/In on HV side 5…50%
Operate time t01> on HV side 0.03…100 s
Basic start ratio P 2/In on LV side 5…50%
Operate time setting t02> on LV side 0.03…100 s
Correction range of HV side neutral connection CT ratio I01/In 0.40…1.50
Correction range of LV side neutral connection CT ratio I02/In 0.40…1.50
Operate time at minimum delay (including heavy-duty output relays) 30…40 ms
Operation accuracy ±4% of set value or
±2% of In
Circuit-breaker failure protection
Operate time 0.1…1.0 s
Integrated disturbance recorder
Recording length 30 cycles
Recording memory capacity 1 recording = 30 cycles
Sampling frequency 40 samples/cycle
Signals to be recorded 8 analog signals
12 digital signals
Triggering when the selected digital is activated
signal
when the selected digital resets
signal
Length of recording preceding triggering 0…30 cycles
ABB Network Partner Stabilized differential relay SPAD 346 C
1MRS 750398-MBG
Page 7

Table 7: Relay module SPCJ 4D28, overcurrent unit

Features Stage I> Stage I>> Stage I>>>
Start current at definite time 0.5…5.0 × In 0.5…40.0 × In and 0.5…40.0 × In and
∞ ∞
at inverse time 0.5…2.5 × In – –
Start time, typically 70 ms 40 ms 40 ms
Operate time at definite time 0.05…300 s 0.04…300 s 0.04…30 s
characteristic
Time/current characteristic at inverse Extremely inverse – –
time mode Very inverse
Normal inverse
Long-time inverse
RI type inverse
RXIDG type
inverse
Time multiplier k 0.05…1.0 – –
Reset time, typically 40 ms 40 ms 40 ms
Retardation time <30 ms
Reset ratio, typically 0.96
Operate time accuracy at definite time ±2% of set value or ±25 ms
mode
Accuracy class index E at inverse time 5 – –
mode
Operation accuracy ±3% of set value ±3% of set value ±3% of set value

Table 8: Relay module SPCJ 4D28, earth-fault and phase discontinuity unit
Features Stage I0> Stage I0>> Stage ∆I>
Start current 0.1…0.8 × In 0.1…10.0 × In and 10…100% and ∞
∞
Start time, typically 70 ms 50 ms 150 ms
Operate time at definite time 0.05…300 s 0.05…300 s 1…300 s
characteristic
Time/current characteristic at inverse Extremely inverse – –
time mode Very inverse
Normal inverse
Long-time inverse
RI type inverse
RXIDG type
inverse
Time multiplier k 0.05…1.0 – –
Reset time, typically 40 ms 40 ms 80 ms
Retardation time <30 ms <30 ms –
Reset ratio, typically 0.96 0.96 0.90
Operate time accuracy at definite time ±2% of set value or ±25 ms
mode
Accuracy class index E at inverse time 5 – –
mode
Operation accuracy ±3% of set value ±3% of set value ±1 unit ±3% of set
value
ABB Network Partner Stabilized differential relay SPAD 346 C
1MRS 750398-MBG
Page 8

Technical data (cont’d) Table 9: Data communication

Transmission mode Fibre-optic serial bus
Data code ASCII
Data transfer rate, selectable 4800 or 9600 Bd
Electrical/optical bus connection module powered for plastic core cables SPA-ZC 21BB
from the host relay for glass fibre cables SPA-ZC 21MM
Electrical/optical bus connection module powered for plastic core cables SPA-ZC 17BB
from the host relay or from an external power source for glass fibre cables SPA-ZC 17MM

Table 10: Tests and standards

Test voltages Dielectric test voltage (IEC 255-5) 2 kV, 50 Hz, 1 min
Impulse test voltage (IEC 255-5) 5 kV, 1.2/50 µs, 0.5 J
Insulation resistance (IEC 255-5) >100 MΩ, 500 V dc
Interference tests High frequency disturbance test 2.5 kV, 1 MHz
(IEC 255-22-1), common mode
High frequency disturbance test 1.0 kV, 1 MHz
(IEC 255-22-1), differential mode
Electrostatic discharge (IEC 255- 8 kV
22-2 and IEC 801-2, class III), air
discharge
Electrostatic discharge (IEC 255- 6 kV
22-2 and IEC 801-2, class III),
contact discharge
Fast transients (IEC 255-22-4, 4 kV
class III and IEC 801-4, level IV),
power supply inputs
Fast transients (IEC 255-22-4, 2 kV
class III and IEC 801-4, level IV),
other inputs
Environmental conditions Service temperature range -10…+55°C
Long term damp heat withstand <95%, +40°C, 56 d/a
(IEC 68-2-3)
Temperature influence 0.1%/°C
Damp heat test (IEC 68-2-30) 93…95%, +55°C, 6 cycles
Transport and storage -40…+70°C
temperature range (IEC 68-2-8)
Degree of protection by enclosure IP 54
of flush mounting relay case (IEC
529)
Weight of fully equipped relay ~6 kg
ABB Network Partner Stabilized differential relay SPAD 346 C
1MRS 750398-MBG
Page 9

Block diagram

P2 P1 P1 P2
L1

L2

L3
S2 S1 S1
S2
Rx Tx
S1 P1 P1 S1

SPA-ZC_
S2 S2
P2 P2

+ (~)
Uaux
- (~)

X0/15

X0/19

X0/21
X0/14
X0/26
X0/27

X0/13

X0/16

X0/18
X0/25

X0/17

X0/20
X0/38
X0/39
X0/37

X2/1
X2/2
X0/2

X0/5

X0/8
X0/1

X0/3
X0/4

X0/6
X0/7

X0/9

U5
≅
5A

5A

1A

1A
5A

1A

5A

1A
1A

5A

5A

1A
1A

1A

5A

5A
N

N
N

N
N

N
N

+ - SERIAL
PORT
I/O

X2/16
X2/17 IRF
IRF X2/18
U6 +

X2/14
SPAD 346 C Y/∆ U1 IRF SS1 X2/15
+
SS1
SS2 X2/11
Y/∆ SS3 X2/12
BS1 3∆I> SS4 SS2 X2/13
BS2 TS1 +
BS3 3∆I>>
U4 TS2
X1/1 BS4 TS3 X2/9
TS4 X2/10
X1/2 BS1 BS5 SS3
I/O +

X1/3 U2 IRF X2/7

SS1 X2/8
X1/4 BS2 SS4
SS2 +
SS3
X1/5 BS1 ∆I 01 > SS4 X2/5
TS1 TRIP
X1/6 BS3 BS2 ∆I 02 > TS1
X2/6
BS3 TS2 +
X1/7 TS3
BS4 TS4
X2/3
X1/8 BS4 BS5 I/O TRIP
X2/4
TS2
U3 IRF +
X1/9
SS1
X1/10 BS5 SS2 X1/15
3I> SS3 X1/16
TRIP
BS1 I SS4 X1/17
BS2 TS1 X1/18
BS3
∆I> TS2 TS3 +
TS3
TS4 X1/11
I/O X1/12
TRIP
X1/13
X1/14
TS4 +

Fig. 1 Block diagram and sample connection diagram

ABB Network Partner Stabilized differential relay SPAD 346 C
1MRS 750398-MBG
Page 10

Mounting and Flush mounting

dimensions 293
226 259 34 214 ±1
30 229

139 ±1
Panel
162

136
cut-out

dim300

Fig. 2 Flush-mounting relay case (dimensions in mm)

Semi-flush mounting
a b

Raising frame a b
SPA-ZX 301 219 74
SPA-ZX 302 179 114
SPA-ZX 303 139 154
SFM300_1
Fig. 3 Semi-flush mounting relay case (dimensions in mm)

Mounting in 19 inch cabinets Projecting mounting

and frames When projecting mounting is preferred, a
An ancillary mounting plate, height 4U relay case type SPA-ZX 317 is used. The
(~177 mm), is recommended to be used when relay case for projecting mounting is pro-
the protection relays are to be mounted in 19 vided with front connectors.
inch frames or cabinets. The ancillary mount-
ing plate type SPA-ZX 304 accommodates
two size 300 relays and type SPA-ZX 305 one
size 300 relay.

SPA-ZX304 SPA-ZX306
SPA-ZX305 SPA-ZX307
SPA-ZX201 SPA-ZX317
SPA-ZX318
+0,4 242 306
482,6 –0 (19")
197
ø6
177 –0 (4U)
101,6

7
+0,4

312
292

6
197 98
21,5

304_5_6

Fig. 4 Mounting cabinets and frames as well as projecting mounting (dimensions in mm)
ABB Network Partner Stabilized differential relay SPAD 346 C
1MRS 750398-MBG
Page 11

Ordering When ordering, please specify:

Ordering information Ordering example
1. Type designation and quantity SPAD 346 C, 5 pieces
2. Order number RS 621 002-AA
3. Rated values In=5 A, fn=50 Hz
4. Auxiliary voltage Uaux =110 V dc
5. Accessories -
6. Special requirements -

Order numbers
Stabilized differential relay SPAD 346 C_
SPAD 346 C complete RS 621 002-AA, CA, DA, FA
SPAD 346 C1, incl. modules SPCD 3D53 and RS 621 003-AA, CA, DA, FA
SPCD 2D55
SPAD 346 C2, incl. modules SPCD 3D53 and RS 621 004-AA, CA, DA, FA
SPCJ 4D28
SPAD 346 C3, incl. module SPCD 3D53 RS 621 005-AA, CA, DA, FA
SPAD 346 C4, incl. modules SPCD 2D55 and RS 621 006-AA, CA, DA, FA
SPCJ 4D28
SPAD 346 C5, incl. module SPCD 2D55 RS 621 007-AA, CA, DA, FA
SPAD 346 C6, incl. module SPCJ 4D28 RS 621 008-AA, CA, DA, FA
The last two letters of the order number indicate the AA equals fn = 50 Hz and Uaux = 80…265 V ac/dc
rated frequency fn and the auxiliary voltage Uaux of CA equals fn = 50 Hz and Uaux = 18…80 V dc
the relay as follows:
DA equals fn = 60 Hz and Uaux = 80…265 V ac/dc
FA equals fn = 60 Hz and Uaux = 18…80 V dc

Stabilized differential relay SPAD 346 C_ including a test adapter type RTXP18
SPAD 346 C complete RS 621 202-AA, CA, DA, FA
SPAD 346 C1, incl. modules SPCD 3D53 and RS 621 203-AA, CA, DA, FA
SPCD 2D55
SPAD 346 C2, incl. modules SPCD 3D53 and RS 621 204-AA, CA, DA, FA
SPCJ 4D28
SPAD 346 C3, incl. module SPCD 3D53 RS 621 205-AA, CA, DA, FA
SPAD 346 C4, incl. modules SPCD 2D55 and RS 621 206-AA, CA, DA, FA
SPCJ 4D28
SPAD 346 C5, incl. module SPCD 2D55 RS 621 207-AA, CA, DA, FA
SPAD 346 C6, incl. module SPCJ 4D28 RS 621 208-AA, CA, DA, FA
The last two letters of the order number indicate the AA equals fn = 50 Hz and Uaux = 80…265 V ac/dc
rated frequency fn and the auxiliary voltage Uaux of CA equals fn = 50 Hz and Uaux = 18…80 V dc
the relay as follows:
DA equals fn = 60 Hz and Uaux = 80…265 V ac/dc
FA equals fn = 60 Hz and Uaux = 18…80 V dc

References Additional information

Colour brochure “Stabilized differential relay 1MRS 750022-MDS EN
SPAD 346 C”
User’s manual and technical description “Stabilized 1MRS 750096-MUM EN
differential relay SPAD 346 C”
ABB Network Partner Stabilized differential relay SPAD 346 C
1MRS 750398-MBG
Page 12

ABB Substation Automation Oy

P.O. Box 699
FIN-65101 Vaasa
Finland
Telephone: +358 10 224 000
Fax: +358 10 224 1094