SCL Range, Control Circuit Transformers

SCL Range Control Circuit Transformers offering 230V and 400V with adjustment tappings. Designed and manufactured to comply with IEC61558.

This high quality product is manufactured using automated winding and welding machines; they offer good access to the four-hole fixing, finger-proof terminals and full varnish impregnation to protect against humidity.

Control Transformer Class 1 Isolation Transformer with Earth Screen between Primary and Secondary
Standard IEC / BS-EN 61558
Primary Voltages 220-230-240-380-400-415V
Secondary Voltages One of the following. 12V, 24V (12-0-12V), 48V, 110V(55-0-55V), 230V
Frequency 50/60Hz
Insulation Class B
Insulation Resistance > 5 Meg Ω
Dielectric Strength Winding to Earth > 2.5kV
Dielectric Strength Primary to Secondary > 2.5kV
Primary to Earth > 2.5kV
Secondary to Earth > 2.5kV
Ambient Temperature 40℃

Transformer Circuit Protection

Transformers must be protected against short circuit and overload.

Primary Circuit

The primary side of the Transformer should be protected against short circuit thereby cutting the supply voltage in the event of a short circuit fault. The rating of the primary protection device has to take into account the high inrush current during energizing of the Transformer.

The table below gives suggested protection values to avoid nuisance tripping on inrush.

Rating VA Primary Volts Amps Fuse Type C MCB Type D MCB Primary Volts Amps Fuse Type C MCB Type D MCB
50 230 0.21 1 1 1 415 0.12 500mA 1 1
75 230 0.27 1 1 1 415 0.15 500mA 1 1
100 230 0.43 1 2 1 415 0.24 1 1 1
150 230 0.65 2 2 1 415 0.36 1 1 1
200 230 0.86 2 6 2 415 0.48 1 2 1
250 230 1.09 3.15 6 2 415 0.60 2 2 1
300 230 1.2 3.15 6 3 415 0.72 2 2 2
500 230 2.17 4 10 6 415 1.20 3.15 6 4
750 230 3.26 6 10 6 415 1.80 3.15 6 4
1000 230 4.34 8 10 6 415 2.40 5 6 4
1500 230 6.52 10 16 10 415 3.61 6 10 6
2000 230 8.69 12 16 10 415 4.82 10 10 6
2500 230 10.86 16 25 16 415 6.02 10 16 10

Secondary Circuit

The secondary circuit should be protected against short circuit and overload.

The value of the protection should be the same or less than the rated output current.

Part No. VA A B C D E Weight kg % Reg. Watts Inrush VA For 10% Volt Drop Inrush VA For 5% Volt Drop
SCL25 66 68 77 50 44 0.7 11 6 48 36
SCL50 76 70 86 56 47 1.1 9.8 9 105 77
SCL75 76 76 86 56 53 1.4 8.9 11 135 102
SCL100 84 78 95 64 63 2.2 8.4 14 250 175
SCL150 96 76 102 84 65 3.1 6.7 18 375 260
SCL200 96 86 102 84 72 4 5.8 21 550 375
SCL250 96 101 102 84 90 5 5.6 27 720 470
SCL300 120 88 122 90 73 6 5.3 31 870 585
SCL400 120 100 122 90 85 6.75 5.0 30 1200 790
SCL500 120 120 122 90 106 7.5 4.1 31 1700 1100
SCL750 150 110 140 122 90 10 5.2 60 2200 1475
SCL1000 150 161 140 122 106 13 3.3 67 4000 2500
SCL1500 150 188 140 122 134 16 3.2 88 6200 3850
SCL2000 192 172 180 160 125 18 3.3 100 8060 5030
SCL2500 192 192 180 160 153 24 2.6 120 12100 7300

Voltage Options and Part Number

Winding Voltage
Primary 220-230-240-380-400-415V
Secondary 0-12V
24V Centre tapped (12-0-12V)
0-48V
110V Centre tapped (55-0-55V)
0-230V

For a 100VA Transformer with an output of 110V the Part Number would be SCL100110.

Power Rating Calculation

To choose the size of Transformer required for an application the total inrush VA must be calculated. This figure is then applied to the table above with the maximum allowable voltage drop taken into account. For example, for a calculated inrush of 2,100VA the appropriate transformer is as follows:

  1. For 10% drop in output volts during inrush, choose 750 VA
  2. For 5% drop in output volts during inrush, choose 1000 VA

Consideration must also be given to the continuous VA requirement.

Purchasing

Boardman Transformers' core range of products are available to purchase through many of the leading UK and international distributors and we are always happy to provide details of where our transformers may be bought.

Should your requirements be of a more specialist or bespoke nature, we ask that you contact us directly to speak to a member of our team.