transformer is very useful for high and low voltage work in the
laboratory, shop, and field, for testing, measuring, and
calibrating. The excellent accuracy and the One-to-One
calibrating feature of the P-5000-4 transformer make it well
suited as a standard for calibrating work. Because of the
particular current ranges provided by this transformer (from 5
amperes to 5000 amperes), the P-5000-4 is especially well suited
for testing current transformers for ratio errors and phase
angle with the Knopp Transformer Comparator.
The range of a 5 ampere
meter or wattmeter can be accurately extended by this
transformer to cover all current values between 5 amperes and
5000 amperes, with the advantage that the ammeter need not be
used below the half-scale point.
The Knopp Precision
Multirange Transformers have excellent ratio and phase angle
performance, both inter-range and overall. The P-5000-4
transformer is furnished for a specified secondary burden, which
can be any value between 0 and 25 volt-amperes. For example, with
a secondary burden of 15 volt-amperes, the ratio of this
transformer at 100% of full load current is well within .02% and
the phase angle is within 1 minute, and at 10% of full load
current the performance is within .04% and 2 minutes.
A total of 23 primary
ranges are provided. The self-contained primary ranges are: 5,
10, 15, 20, 25, 50, 75, 100, 150, and 200 amperes, and the
following primary ranges can be obtained with an inserted
primary of 1 primary turn: 400, 500, 600, 750, 800, 1000, 1200,
1500, 2000, 2500, 3000, 4000, and 5000 amperes. The secondary is
The transformer housing
insulates the inserted primary from the transformer windings for
2500 volt circuits. The wound primary is for use on 250 volt
The transformer can be
calibrated in itself by the Knopp One-to-One method, by direct
comparison of the primary current against the secondary current.
The Type P-50004 Knopp
Precision Multirange Transformer weighs 45 lbs.; and the
bakelite case, which is fitted with a leather handle, measures
13.25" wide, 5.25" deep, and 14.25" high. The
center opening is 3" in diameter. The secondary is provided
with a convenient short-circuiting switch.
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more information about the
P-5000 and P-5000-4 CT's.