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Transformers for use with Contactors / Relays

Transformers manufactured by TEC for use in initial high inrush v.a. such as contactor or relay circuits, are designed with open circuit voltage 5% maximum above specified value.

The table below shows the maximum peak initial loads permissible for limited volt drop below the specified voltage. The continuous v.a. selected is that which will take final and/or initial v.a. whichever is the greater.

Continuous

VA

NL-FL

Voltage Drop

at rated VA
Peak
5%
(initial) VA
7.5%
Max value
10%
at UPF for
15%

50 9.6% 50 60 75 100

100 6.8% 107 140 180 250

150 6.5% 165 210 275 400

250 4.9% 400 525 700 950

350 4.8% 500 700 875 1200

400 3.9% 750 975 1250 1750

500 3.7% 1000 1300 1600 2100

600 3.15% 1300 1750 2200 3000

750 2.8% 1800 2400 3100 4250

1000 2.7% 2600 3500 4250 5750

1500 2.8% 3700 5000 6300 8600

2000 2.35% 6000 8000 10000 14000

2500 2.1% 8000 11000 14000 20000

3000 2.05% 10000 13500 17000 24000

3500 1.9% 12000 16000 20000 28000

4000 2.0% 13500 17500 22000 31000

4500 1.8% 16000 22000 27500 38000

5000 1.5% 21000 28500 36000 50000