medium voltage devices _ range products
TRANSCRIPT
Siemens Power Engineering Guide · Transmission & Distribution2/66
Medium-Voltage DevicesProduct Range
Devices formedium-voltage switchgear
With the equipment program for switch-gear Siemens can deliver nearly everydevice which is required in the medium-voltage range between 7.2 and 36 kV.Fig. 110 gives an overview about the avail-able devices and their main characteristics.All components and devices conform tointernational and national standards,as there are:
Vacuum circuit breakers
■ IEC 56■ IEC 694■ BS5311■ DIN VDE 0670
Vacuum switches
■ IEC 265-1■ DIN VDE 0670, Part 301in combination with Siemens fuses:■ IEC 420■ DIN VDE 0670, Part 303
Vacuum contactors
■ IEC 470■ DIN VDE 0660, Part 103■ UL 347
Switch disconnectors
■ IEC 129■ IEC 265-1■ DIN VDE 0670, Part 2■ DIN VDE 0670, Part 301
HV HRC fuses
■ IEC 282■ DIN VDE 0670, Part 4
Current and voltage transformers
■ IEC 185, 186■ DIN VDE 0414■ BS 3938, 3941■ ANSI C57.13
For further information please contact:
Fax: ++ 49 - 91 31 - 73 46 54
Fig. 110: Equipment program for medium-voltage switchgear
Short-timecurrent(3s)
[kA]
3AH
3AF3AG
Type Ratedvoltage
[kV]
Short-circuitcurrent
[kA]
Indoor and outdoorcurrent and voltagetransformers
Device
Indoor vacuumcircuit breaker
Outdoor vacuumcircuit breaker
Modular assembly setwith indoor VCB
Indoor vacuum switch
Indoor vacuumcontactor
Vacuum interrupter
Indoor switchdisconnector
Indoor disconnectingand grounding switch
HV HRC fuses
Fuse bases
Indoor post insulators,bushings
7.2 … 36
12, 36
7.2 … 15
7.2 … 24
3.6 … 12
7.2 … 40.5
7.2 … 24
7.2 … 36
7.2 … 36
7.2 … 36
3.6 … 36
12 … 36
3CG
3TL
VS
3CJ
3D
3GD
3GH
3FA
3M
13.1 … 63
25
25 … 44
–
–
12.5 … 72
–
–
31.5 … 80
–
–
13.1 … 63
25
25 … 44
16 … 20
8 (1s)
12.5 … 72
16 … 20 (1s)
16 ... 63 (1s)
–
–
–
–
44peak withstandcurrent
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Medium-Voltage DevicesProduct Range
PageRatedcurrent
[A]
2/68�
2/72
2/73
2/74
2/76
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2/78
2/79
2/80
2/80
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2/82
mechanical
Applications/remarksOperating cycles
All applications, e.g. overhead lines, cables, transformers,motors, generators, capacitors, filter circuits, arc furnaces
All applications, e.g. overhead lines, cables, transformers,motors, generators, capacitors, filter circuits
Original equipment manufacturer (OEM) and retrofit
All applications, e.g. overhead lines, cables, transformers,motors, capacitors; high number of operations; fusesnecessary for short-circuit protection
All applications, especially motors with very high numberof operating cycles
For circuit breakers, switches and gas-insulated switchgear
Small number of operations, e.g. distribution transformers
Protection of personnel working on equipment
Short-circuit protection; short-circuit current limitation
Accommodation of HV HRC fuse links
Insulation of live parts from another,carrying and supporting function
Measuring and protection
with ratedcurrent
with short-circuit current
25 … 100
30 … 50
–
–
–
25 … 100
–
–
–
–
–
–
10,000 …30,000
10,000
–
10,000
0.25x105 ... 2x106
10,000 …30,000
800 … 4000
1600
1250 … 3150
800
400 … 450
800 … 4000
630
400 … 2500
6.3 … 250
400
–
–
20
–
–
–
–
–
1000
–
–
–
–
–
10,000 …120,000
10,000
–
10,000
1x106 ... 3x106
10,000 …30,000
Siemens Power Engineering Guide · Transmission & Distribution2/68
Indoor vacuum circuit breakerstype 3AH
The 3AH vacuum circuit breakers arethree-phase medium-voltage circuit break-ers for indoor installations.As standard circuit breakers they are avail-able for the entire medium-voltage range.Circuit breakers with reduced pole centerdistances, circuit breakers for very highnumbers of switching cycles and single-phase versions are part of the program.The following breaker types are available:■ 3AH1 – the maintenancefree circuit
breaker which covers the rangebetween 7.2 kV and 24 kV. It hasa lifetime of 10,000 operating cycles
■ 3AH2 – the circuit breaker for 60,000operating cycles in the range between7.2 kV and 24 kV
■ 3AH3 – the maintenancefree circuitbreaker for high breaking capacities inthe range between 7.2 kV and 36 kV.It has a lifetime of 10,000 operatingcycles
■ 3AH4 – the circuit breaker for up to120,000 operating cycles
■ 3AH5 – the economical circuit breaker inthe lower range for 10,000 maintenance-free operating cycle
The 3AH circuit breakers are suitable for:■ Rapid load transfer, synchronization■ Automatic reclosing up to 31.5 kA■ Breaking short-circuit currents with
very high initial rates of rise of the recov-ery voltage
■ Switching motors■ Switching transformers and reactors■ Switching overhead lines and cables■ Switching capacitors■ Switching arc furnaces
Fig. 111: The complete 3AH program
Rated short-circuit breakingcurrent [kA]
7.2
12
15
17.5
24
36
13.1 16 20 25 31.5 40 50 63
800 800-1250
800-2500
800-1250
1250-3150
1250-4000
1250-2500
–-2500
Rated voltage[kV]
3AH1 3AH2 3AH3 3AH4 3AH5
800-1250
800-1250
1250-3150
Rated current[A]
Medium-Voltage DevicesType 3AH
Properties of 3AH circuit breakers:
No relubrication
Nonwearing material pairs at the bearingpoints and nonaging greases make relubri-cation superfluous on 3AH circuit breakersup to 10,000 operating cycles, even afterlong periods of standstill.
High availability
Continuous tests have proven that the3AHs are maintenancefree up to 10,000operating cycles: accelerated temperature/humidity change cycles between –25 and+60 °C prove that the 3AH functions relia-bly without maintenance.
Assured quality
Exemplary quality control with some hun-dred switching cycles per circuit breaker,certified to DIN/ISO 9001.
No readjustment
Narrow tolerances in the production ofthe 3AH permanently prevent impermissi-ble play: even after frequent switchingthe 3AH circuit breaker does not need tobe readjusted up to 10,000 operatingcycles.
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Fig. 112: Vacuum circuit breakers type 3AH
Fig. 113: Front view of vacuum circuit breaker 3AH1 with 160-mm pole center distance. Available up to 17.5 kV
Medium-Voltage DevicesType 3AH
Advantages of thevacuum switching principle
The most important advantages of theprinciple of arc extinction in a vacuum havemade the circuit breakers a technically su-perior product and the principle on whichthey work the most economical extinctionmethod available:■ Constant dielectric:
In a vacuum there are no decompositionproducts and because the vacuum inter-rupter is hermetically sealed there areno environmental influences on it.
■ Constant contact resistance:The absence of oxidization in a vacuumkeeps the metal contact surface clean.For this reason, contact resistance canbe guaranteed to remain low over thewhole life of the equipment.
■ Large total current:Because there is little burning of con-tacts, the rated normal current can beinterrupted up to 30,000 times, theshort-circuit breaking current an averageof 50 times
■ Small chopping current:The chopping current in the Siemensvacuum interrupter is only 4 to 5 A dueto the use of a special contact material.
■ High reliability:The vacuum interrupters need no seal-ings as conventional circuit breakers.This and the small number of movingparts inside makes it extremely reliable.
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Fig. 114a: Dimensions of typical vacuum circuit breakers type 3AH (Examples)
604532
210 210
520
190
105
437 473
60
604538
210 210
565
109
437583
105
190550
275 275662708 565
190
105
437535
60
Dimensions in mm
Dimensions in mm
Dimensions in mm
20 kA, up to 1250 A25 kA, up to 1250 A
3AH1,12 kV
16 kA, up to 1250 A,20 kA, up to 1250 A,25 kA, up to 1250 A
3AH1,24 kV
31.5 kA, 2500 A,40 kA, 2500 A
3AH1, 3AH2,12 kV
Medium-Voltage DevicesType 3AH
Siemens Power Engineering Guide · Transmission & Distribution 2/71
708 595670
275275190
105
437
109
610
648
211 483
564 733
750275 275
25 kA, 2500 A
63 kA, 4000 A
3AH3,12 kV
31.5 kA, 2500 A,40 kA, 2500 A
3AH1, 3AH2,24 kV
3AH3, 3AH4,36 kV
776
820350 350
853
526211
612
564 1000791
Dimensions in mm
Dimensions in mm
Dimensions in mm
Medium-Voltage DevicesType 3AH
Fig. 114b: Dimensions of typical vacuum circuit breakers type 3AH (Examples)
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Outdoor vacuum circuitbreakers type 3AF and 3AG
The Siemens outdoor vacuum circuitbreakers are structure-mounted, easy-to-install vacuum circuit breakers for use insystems up to 36 kV. The pole construc-tion is a porcelain-clad construction similarto conventional outdoor high-voltageswitchgear. The triple-pole circuit breakeris fitted with reliable and well proven vacu-um interrupters. Adequate phase spacingand height have been provided to meetstandards and safety requirements.It is suitable for direct connection to over-head lines.The type design incorporates a minimumof moving parts and a simplicity of assem-bly assuring a long mechanical and electri-cal life. All the fundamental advantages ofusing vacuum interrupters like low operat-ing energy, lightweight construction, vir-tually shockfree performance leading toease of erection and reduction in founda-tion requirements, etc. have been retained.The Siemens outdoor vacuum circuitbreakers are designed and tested to meetthe requirements of IEC 56/IS 13118.
Advantages at a glance
■ High reliability■ Negligible maintenance■ Suitable for rapid autoreclosing duty■ Long electrical and mechanical life■ Completely environmental-friendly
Fig. 115: Outdoor vacuum circuit breakertype 3AF for 36 kV
Fig. 117: Dimensions of outdoor circuit breaker type 3AF for 36 kV
Fig. 116: Ratings for outdoor vacuum circuit breakers
12Rated voltage
Rated frequency
Rated lightning-impulse withstand voltage
Rated power-frequencywithstand voltage (dry and wet)
Rated short-circuitbreaking current
Rated short-circuitmaking current
Rated current
75
28
25
63
1600
50/60
36
170
70
25
Type 3AG
Technical data
Type 3AFVacuum circuit-breaker type
50/60
63
1600
[kV]
[Hz]
[kV]
[kV]
[kA]
[kA]
[A]
1830
1217
725 725190
19301730
650450
31052510
3710 3748
285 285
Front view Side view
Dimensions in mm
Medium-Voltage DevicesType 3AF/3AG
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Modular assembly sets withindoor vacuum circuit breakers
The modular assembly sets are especiallysuitable for retrofit applications and for theuse by original equipment manufacturers(OEM).The withdrawable assembly sets consist ofparts of type-tested, metal-clad, air-insulat-ed medium-voltage primary distributionswitchgear. The circuit-breaker compart-ment can be integrated in the completebay as individually required.The centerpiece of the set is a medium-voltage vacuum circuit breaker, incorporat-ing all benefits of vacuum switchgeartechnology:■ High reliability■ Negligible maintenance■ Long electrical and mechanical life■ Completely environment-friendly■ Suitable for all switching dutiesUse of these parts allows the OEM to uti-lize Siemens know-how in the constructionof air-insulated switchgear, with all the con-sequent advantages, such as:■ Components type-tested to IEC, devel-
oped and manufactured to DIN/ISO 9001■ Maximum flexibility in the manufacturing
process■ Wide product range
Ratingsfor withdrawable truck shown in Fig. 118
7.2 kV to 15 kV rated voltage1250 A to 3150 A rated current25 kA to 44 kA rated short-circuit
breaking current
Fig. 118: Withdrawable truck with vacuum circuit breaker (Example)
Medium-Voltage DevicesModular Assembly Sets
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Indoor vacuum switchestype 3CG
The 3CG vacuum switches are multipur-pose switches conforming to IEC 265-1and DIN VDE 0670 Part 301.With these, all loads can be switched with-out any restriction and with a high degreeof reliability. The electrical and mechanicaldata are greater than for conventionalswitches. A rated current of 800 A, forexample, can be interrupted 10,000 timeswithout maintenance.The operating mechanism needs to belubricated only every 10 years.The vacuum switch is therefore extremelyeconomical.Vacuum switches are suitable for thefollowing switching duties:■ Overhead lines■ Cables■ Transformers■ Motors■ Capacitors■ Switching under ground-fault conditions
3CG switches can be combined with allSiemens fuses (250 A) and comply withthe specifications of IEC 420 andDIN VDE 0670 Part 303.
Fig. 119: Ratings for vacuum switches type 3CG
Fig. 120: Vacuum switch type 3CG for 24 kV, 800 A
Medium-Voltage DevicesType 3CG
Rated voltage U
Rated lightning-impulsewithstand voltage Ul,
Rated short-circuit makingcurrent I ma
Rated short-time current I m (3s)
Rated normal current I n
Rated ring-main breakingcurrent I c 1
Rated transformer breaking current
Rated capacitor breaking current
Rated cable-chargingbreaking current I c
Rated breaking current forstalled motors I d
Inductive switching capacity(cos ϕ ≤ 0.15)
Switching capacity underground fault conditions:– Rated ground fault breaking current I e– Rated cable-charging breaking current– Rated cable charging breaking current with superimposed load current
Number of switching cycles with I n
[kV]
[kV]
[kA]
[kA]
[A]
[A]
[A]
[A]
[A]
[A]
[A]
[A][A]
[A]
Technical data
12
75
50
20
800
800
10
800
63
1600
1600
63063
63+800
10,000
15
95
50
20
800
800
10
800
63
1250
1250
63063
63+800
10,000
24
125
40
16
800
800
10
800
63
–
1250
63063
63+800
10,000
7.2
60
50
20
800
800
10
800
63
2500
2500
63063
63+800
10,000
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Fig. 121: Dimensions of vacuum switch type 3CG (Examples)
7.2 and 12 kV switch
24 kV switch
630
275 275
379
684
708
537
435
43170
597
530
264
210 210
568
592
435
43170
492
482
Dimensions in mm
Dimensions in mm
Medium-Voltage DevicesType 3CG
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280 mm
325 mm
340 mm
Fig. 122: Vacuum contactor type 3TL6 for fixedmounting
Vacuum contactorsType 3TL
The three-pole vacuum contactors type3TL are for medium-voltage systems be-tween 3.6 kV and 12 kV and incorporate asolenoid-operated mechanism for highswitching frequency and unlimited closingduration.They are suitable for the opera-tional switching of AC devices in indoorsystems and can perform, for example, thefollowing switching duties:■ Switching of three-phase motors in
AC-3 and AC-4 operation■ Switching of transformers■ Switching of capacitors■ Switching of ohmic loads
(e.g. arc furnaces)
3TL vacuum contactors have the followingfeatures:■ Small dimensions■ Long electrical life
(up to 106 operating cycles)■ Maintenancefree■ Vertical or horizontal mounting
The vacuum contactors comply with thestandards for high-voltage AC contactorsbetween 1 kV and 12 kV according to IECPublication 470-1970 and DIN VDE 0660Part 103.3TL contactors also comply with ULStandard 347.
The vacuum contactors are available indifferent designs:■ Type 3TL6 with compact dimensions
and an electrical lifetime of 1x106 operat-ing cycles
■ Type 3TL8 with slender design and anelectrical lifetime of 0.25x106 operatingcycles
In the withdrawable unit, the 3TL6 vacuumcontactor can be grouped together andelectrically connected with fuse carriers forHV HRC fuse links according to DIN/BSand also with overvoltage limiters.
Fig. 123: Vacuum contactor type 3TL6 mounted onwithdrawable unit
Fig. 124: Ratings for vacuum contactors type 3TL
Medium-Voltage DevicesType 3TL
Fig. 125: Vacuum contactor type 3TL8 for fixedmounting
780 mm
1200 mm
605 mm
390 mm
375 mm
220 mm
Rated voltage Ue
Rated frequency
Rated normal current I e
Switching capacity according toutilization category AC-4 (cos ϕ = 0.35)Rated making currentRated breaking current
Mechanical life of the contactorswitching cycles
Mechanical life of the vacuuminterrupter – switching cycles
Electrical life of the vacuum interrupter(switching cycles with rated current)
Vacuum contactor type
[kV]
[Hz]
[A]
[A]
Technical data
12
3TL 65
7.2
3TL 61
3.6
50/60
45003600
3TL 60
7.2
50/60
40003200
3TL 81
450 400
1 x 106
1 x 106
1 x 106
3 x 106
2 x 106
1 x 106
3 x 106
2 x 106
1 x 106
1 x 106
0.25 x 106
0.25 x 106
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Medium-Voltage DevicesType VS
Vacuum interrupters
Vacuum interrupters for the medium-volt-age range are available from Siemens forall applications on the international marketfrom 1 kV up to 40.5 kV.
Applications
■ Vacuum circuit breakers■ Vacuum switches■ Vacuum contactors■ Transformer tap switches■ Circuit breakers for railway applications■ Autoreclosers■ Special applications, e.g. in nuclear
fusion
Compact design
Vacuum interrupters providea very high switching capacity within verycompact dimensions: e.g. vacuum inter-rupters for 15 kV/40 kA with housingdimensions of 125 mm diameter by168 mm length or for 12 kV/12.5 kA with68 mm diameter by 124 mm length.
Consistant quality assurance
Complete quality assurance (TQM andDIN/ISO 9001), rigorous material checkingof every delivery and 100% tests of theinterrupters for vacuum sealing guaranteereliable operation and the long life ofSiemens vacuum interrupters.
Environmental protection
In the manufacture of our vacuum inter-rupters we only use environmentally com-patible materials, such as copper, ceramicsand high-grade steel.The manufacturing processes do not dam-age the environment. For example, noCFCs are used in production (fulfilling theMontreal agreement), the components arecleaned in a ultrasonic cleaning plant.During operation vacuum interrupters donot affect the environment and are them-selves not affected by the environment.
Know-how for special applications
If necessary, Siemens is prepared to sup-plement our wide standard program byway of tailored, customized concepts.
Fig. 126: Vacuum interrupters from 1 kV to 40.5 kV
Fig. 127: Range of ratings for vacuum interrupters
Interrupters for vacuum circuit breakers
Un
In
Isc
7.2 kV – 40.5 kV
800 A – 4000 A
12.5 kA – 72 kA
Interrupters for vacuum contactors
Un
In
1 kV – 12 kV
450 A
Siemens Power Engineering Guide · Transmission & Distribution2/78
Technical data
7.2
20
50
630
Rated voltage
Rated short-timecurrent
Rated short-circuitmaking current
Rated normal current
[kV]
[kA]
[kA]
[A]
12
20
50
630
15
16
40
630
24
16
40
630
Switch disconnectorstype 3CJ1
Indoor switch disconnectors type 3CJ1 aremultipurpose types and meet all the rele-vant standards both as the basic versionand in combination with (make-proof)grounding switches.The 3CJ1 indoor switch-disconnectorshave the following features:■ A modular system with all important
modules such as fuses, (make-proof)grounding switches, motor operatingmechanism, shunt releases and auxiliaryswitches
■ Good dielectric properties even underdifficult climatic conditions because ofthe exclusive use of standard post insu-lators for insulation against ground
■ No insulating partitions even with smallphase spacings
■ Simple maintenance and inspection
Fig. 128: Switch disconnector type 3CJ1
Fig. 129: Ratings for switch disconnectors type 3CJ1
Medium-Voltage DevicesType 3CJ1
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Medium-Voltage DevicesType 3D
Technical data
12
16 to 63
40 to 160
400 to 2500
Rated voltage
Rated short-timecurrent
Rated short-circuitmaking current
Rated normal current
[kV]
[kA]
[kA]
[A]
24
16 to 31.5
40 to 80
630 to 2500
36
20 to 31.5
50 to 80
630 to 2500
Fig. 130: Disconnecting switch type 3DC
Disconnecting and groundingswitches type 3D
Disconnecting and grounding switchestype 3D are suitable for indoor installationsfrom 12 kV up to 36 kV.Disconnectors are mainly used to protectpersonnel working on equipment and musttherefore be very reliable and safe.This is assured even under difficult climaticconditions.Disconnecting and grounding switchestype 3D are supplied with a manual ormotor drive operating mechanism.
Fig. 131: Ratings for disconnectors type 3DC
Fig. 132: Ratings for grounding switches type 3DE
Technical data
12
20 to 63
50 to 160
Rated voltage
Rated short-timecurrent
Rated peakwithstand current
[kV]
[kA]
[kA]
24
20 to 31.5
50 to 80
36
20 to 31.5
50 to 80
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HV HRC fusestype 3GD
HV HRC (high-voltage high-rupturing-capac-ity) fuses are used as a short-circuit protec-tion in high-voltage switchgear. They pro-tect switchgear and components, such astransformers, motors, capacitors, voltagetransformers and cable feeders, from thedynamic and thermal effects of high short-circuit currents by breaking them as theyoccur.The HV HRC fuse links can only be usedto a limited degree as overload protectionbecause they only operate with certaintywhen their minimum breaking current hasalready been exceeded. Up to this currentthe integrated thermal striker prevents athermal overload on the fuse when used incircuit breaker/fuse combinations.Siemens HV HRC fuse links have the fol-lowing features:■ Use in indoor and outdoor installations■ Nonaging because the fuse element
is made of pure silver■ Thermal tripping■ Absolutely watertight■ Low power lossWith our 30 years of experience in themanufacture of HV HRC fuse links andwith production and quality assurancethat complies with DIN/ISO 9001,Siemens HV HRC fuse links meet thetoughest demands for safety and reliability.
Fuse-bases type 3GH
3GH fuse bases are used to accomodateHV HRC fuse links in switchgear.These fuse bases are suitable for:■ Indoor installations■ High air humidity■ Occasional condensation3GH HV HRC fuse bases are available assingle-phase and three-phase versions.On request, a switching state indicatorwith an auxiliary switch can be installed.
Fig. 134: Ratings for HV HRC fuse links type 3GD
Fig. 133: HV HRC fuse type 3GD
Fig. 135: Fuse bases type 3GH with HV HRC fuse links
Fig. 136: Ratings for fuse bases type 3GH
Technical data
7.2
63 to 80
6.3 to 250
Rated voltage
Rated short-circuitbreaking current
Rated normal current
[kV]
[kA]
[A]
12
40 to 63
6.3 to 160
24
31.5 to 40
6.3 to 100
36
31.5
6.3 to 40
Technical data
3.6/7.2
44
400
Rated voltage
Peak withstandcurrent
Rated current
[kV]
[kA]
[A]
12
44
400
24
44
400
36
44
400
Medium-Voltage DevicesType 3GD/3GH
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Fig. 140: The principle of capacitive voltage indication with the 3FA4 divider post insulator
Medium-Voltage DevicesInsulators and Bushings
Insulators:Post insulators type 3FAand bushings type 3FH/3FM
Insulators (post insulators and bushings)are used to insulate live parts from one an-other and also fulfill mechanical carryingand supporting functions.The materials for insulators are variouscast resins and porcelains. The use ofthese materials, which have proved them-selves over many years of exposure to theroughest operating and ambient conditionsand the high quality standard to DIN/ISO9001, assure the high degree of reliabilityof the insulators.Special ribbed forms ensure high electricalstrength even when materials are deposit-ed on the surface and occasional conden-sation is formed.Post insulators and bushings are manufac-tured in various designs for indoor and out-door use depending on the application.Innovative solutions, such as the 3FA4divider post insulator with an integratedexpulsion-type arrester, provide optimumutility for the customer.Special designs are possible if requestedby the customer.
Fig. 137: Draw-lead bushing type 3FH5/6
Fig. 138: Post insulators type 3FA1/2
C1
V C2
M
A
L
U
U1
U2
LUU1
U2
ConductorOperating voltagePartial voltageacross C1Partial voltage acrossC2 and indicator
C1C2
VAM
Coupling capacitanceUndercapacitance
ArresterIndicatorMeasuring socket
12
65 to90
35 to50
3.75 to25
3.6
60 to65
27 to40
3.75 to16
24
100 to145
55 to75
3.75 to25
36
145 to190
75 to105
3.75 to16
Technical data
Normal voltage
Lightning-impulsewithstand voltage
Rated power-frequencywithstand voltage
Minimum failing load
[kV]
[kV]
[kV]
[kN]
Fig. 139: Ratings for post insulators type 3FA1/2
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Technical data
12
10 to2500
80
Rated voltage
Primary ratedcurrent
Max. thermal ratedshort time current
Sec. thermallimit current
Current transformers Voltage transformers
[kV]
[A]
[kA]
[A]
24
10 to2500
80
36
10 to2500
80
12
5 to 10
24
5 to 13
36
8 to 17
Current and voltagetransformers type 4M
Measuring transformers are electricaldevices that transform primary electricalquantities (currents and voltages) to pro-portional and in-phase quantities which aresafe for connected equipment and operat-ing personnel.The indoor post insulator current and volt-age transformers of the block type haveDIN-conformant dimensions and are usedin air-insulated switchgear. A maximum ofoperational safety is assured even underdifficult climatic conditions by the use ofcycloalyphatic resin systems and provencast-resin technology.Special customized versions (e.g. up to3 cores for current transformers, switcha-ble windings, capacitance layer for voltageindication) can be supplied on request.The program also includes cast-resin insu-lated-bushing current transformers andoutdoor current and voltage transformers.
Fig. 143: Ratings for current and voltage transformers
Fig. 141: Block current transformer type 4MA
Fig. 142: Outdoor voltage transformer type 4MS4
Medium-Voltage DevicesType 4M