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ATM/200 Family

ATT/200 Family

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Home › Products › TransformersAuto Transformers ATM/200 Family

Auto Transformers

ATM/200 Family

Single-Phase Auto Transformers

  • Single-phase auto transformers with ratio 230/400V built according to CE standards CEI 96.1 for power up to 1000VA, and CEI- 14-8 for exceeding powers, or IEC 61558-1 and IEC 61558-2-13
  • Dual terminals for winding "0"
  • Insulation material group F
  • Ambient temperature max. 35 °C
  • Degree of protection IP 00
  • Class F varnish dipped and oven dried
  • Different minimum and maximum voltage ratios, dimensions and prices are available upon request
Reference Number Rated Output Dimensions Drillings Dissipated Power
(W)
Efficiency
(%)
Weight (Kg) Fig.
L P H A B G F
ATM/201 300 VA 96 111 95 68 85 4,5 - 24 92 7,9 1
ATM/202 400 VA 120 81 113 80 55 4,5 - 30 92,5 8,8 1
ATM/203 500 VA 120 101 113 80 75 5,5 - 38 92,4 12,7 1
ATM/204 750 VA 120 111 113 80 85 5,5 - 48 93,6 15,6 1
ATM/205 1kVA 120 136 113 80 110 5,5 - 60 94 19,7 1
ATM/206 1,5 kVA 150 125 163 105 87 5,5 - 82 94,5 26,6 1
ATM/207 2 kVA 150 145 163 105 107 6,5 - 104 94,8 35,2 1
ATM/208 2,5 kVA 180 120 190 130 100 6,5 - 120 95,2 38,4 1
ATM/209 3 kVA 180 130 190 130 110 6,5 - 137 95,4 44,6 1
ATM/210 4 kVA 180 150 190 130 130 6,5 - 171 95,7 57 1
ATM/211 5 kVA 200 134 260 150 96 24 9 151 96,9 18,6 2
ATM/212 6 kVA 200 134 260 150 96 24 9 187 96,8 19,6 2
ATM/213 8 kVA 200 154 260 150 116 24 9 207 97,4 25,6 2
ATM/214 10 kVA 200 164 260 150 126 24 9 244 97,6 29,5 2
ATM/215 12,5 kVA 240 160 310 205 126 24 9 315 97,5 35,2 2
ATM/216 15 kVA 240 170 310 205 136 24 9 372 97,5 39,7 2
ATM/217 20 kVA 240 190 310 205 156 24 9 415 97,9 50 2
ATM/218 25 kVA 280 190 360 234 144 30 10 534 97,8 57,6 2
ATM/219 30 kVA 280 210 360 234 164 30 10 600 98 68,5 2

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.

Download PDF format of this tecnichal sheets

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