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ATM/200 Family

ATT/200 Family

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Home › Products › TransformersAuto TransformersATT/200 Family

Auto Transformers

ATT/200 Family

Three-Phase Auto Transformers

  • Three-phase auto transformers with ratio 230/400V built according to CE standards CEI 96.1 for power up to 5 KVA, exceeding CEI 14.8 or IEC 61558-1 and IEC 61558-2-13
  • Terminal block with neutral
  • Insulation material group II
  • Ambient temperature max. 35 °C
  • Degree of protection IP 00
  • Class H varnish dipped and oven dried
  • Different minimum and maximum voltage ratios, dimensions and prices are available upon request
Reference Number Rated Output
Termica
Dimensions Drillings Dissipated Power
(W)
Efficiency
%
Weight (Kg) Fig.
L P H A B F G
ATT/201 300 VA 120 65 105 105 47 4,.5 10 16 94,6 3,4 3/4
ATT/202 500 VA 120 85 105 105 67 4,5 10 22 95,6 5,2 3/4
ATT/203 1000 VA 180 90 160 125 58 6 13 36 96,4 6,7 3/4
ATT/204 1500 VA 180 110 160 125 78 6 13 51 96,6 9,7 3/4
ATT/205 2000 VA 180 165 160 125 111 6 13 59 96,8 14,0 3/4
ATT/206 2500 VA 240 120 210 200 86 7 18 77 96,9 14,5 3/4
ATT/207 3000 VA 240 120 210 200 86 7 18 88 97 15,2 3/4
ATT/208 4000 VA 240 130 210 200 96 7 18 104 97,4 18,7 3/4
ATT/209 5000 VA 240 140 210 200 106 7 18 123 97,5 21,8 3/4
ATT/210 7500 VA 300 134 260 250 96 9 24 177 97,6 29,6 3/4
ATT/211 10 kVA 300 144 260 250 106 9 24 207 97,9 36,0 3/4
ATT/212 12,5 kVA 300 154 260 250 116 9 24 240 98 41,7 3/4
ATT/213 15 kVA 360 160 310 325 126 9 24 289 98,1 51 3/4
ATT/214 20 kVA 360 170 310 325 136 9 24 347 98,2 60,4 3/4
ATT/215 25 kVA 360 190 310 325 156 9 24 398 98,4 74,3 3-5/4
ATT/216 30 kVA 360 190 310 325 156 9 24 377 98,7 73,9 3-5/4
ATT/217 40 kVA 420 190 360 375 144 10 30 497 98,7 85,7 3/5
ATT/218 50 kVA 420 200 360 375 154 10 30 587 98,8 97,6 3/5
ATT/219 60 kVA 480 210 360 375 164 10 30 675 98,8 109 3/5
ATT/220 80 kVA 480 212 410 440 170 12 30 842 98,9 139 3/5
ATT/221 100 kVA 480 242 410 440 200 12 30 863 99,1 181 3/5
ATT/222 125 kVA 540 290 460 480 244 12 30 1062 99,1 221 3/5
ATT/223 150 kVA 540 290 550 480 244 12 30 1271 99,1 257 3/5
ATT/224 175 kVA 600 310 610 540 266 10 30 1406 99,2 315 3/5
ATT/225 200 kVA 600 330 610 540 286 10 30 1531 99,2 357 3/5
ATT/226 250 kVA 600 350 610 540 306 10 30 1781 99,2 410 3/5
ATT/227 300 kVA 600 370 610 540 326 10 30 2065 99,3 458 3/5
ATT/228 350 kVA 720 230 730 660 274 13 30 2387 99,3 527 3/5
ATT/229 400 kVA 720 250 730 660 294 13 30 2610 99,3 605 3/5
ATT/230 500 kVA 720 280 730 660 310 13 30 3057 99,4 700 3/5
Fig 3 Fig 4 Fig 5

Single and three-phase auto transformers mainly feature a single winding, which works either as a primary or a secondary; thus input/output galvanic insulation does not exist.
The more the ratio between minimum and maximum voltages nears the value 1, the more the auto transformers are inexpensive. Besides the economical aspect, compared to equivalently powered transformers, there are also high efficiency and low working losses to be considered.
To determine the physics dimension of the auto transformer, the core power must be
considered:

PC = PO x (1 – Vm/VM)

(PO = rated output power / Vm = min. voltage / VM = max. voltage)

This value represents the power which is actually transformed, while the other is supplied directly from the mains supply.
The most frequent use is that which requests a voltage adaptation when a galvanic
insulation from mains is not required. A typical example is an apparatus built to work on 380V and the mains supply is 415V.
With all single-phase auto transformers, OV connection is repeated twice to facilitate the wiring and avoid having to insert two wires in the same terminal.
The three-phase auto transformers have a neutral connection in the terminal block, which is advisable to connect to the mains supply neutral (when present), thus avoiding over voltage in respect to earth on the line at a lower voltage.
The most frequently used and traditional is the star-connection, which is also the simplest to make; although triangle, zigzag and other connections are possible.
It is possible to build three-phase auto transformers with special connections, which create a neutral, if this is not already provided by the mains supply, but needed to connect single-phase units; in this case, please contact our technicians to define the exact parameters.

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