DENGENSHA WS-100, Инструкция по эксплуатации

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7
DENGENSHA
(7) To use within maximum input and allowable duty factor
The welding transformer has rated input, maximum input, allowable duty factor, and so
forth. This is the heat capacity of welding transformer prescribed under the cooling
conditions (temperature and quantity of water). This specification indicates the upper
limit of operation of the welding transformer. In excess of this limit, the welding
transformer may be overheated or burnt in some cases. Since the heat capacity of welding
transformer is based predicated on being cooled, the welding transformer may be
overheated under normal operation or burnt in some cases if the cooling condition is
insufficient.
The welding machine and welding transformer should be used within prescribed
maximum input and allowable duty factor without fail. (For details, refer to the
REFERENCE “Maximum Input of Welding Transformer, allowable duty factor”.)
◎
Reference 1
：
Maximum input and allowable duty factor of welding transformers
Rated input P
50
, maximum input P
max
, allowable duty factor

max
, etc. are prescribed for
welding transformers.
Rated input P
50
indicates the input kVA of the welding machine when the duty factor is
assumed to be 50%.
The heat capacity of a welding transformer can be indicated with the following formula,
using the input and duty factor.
Heat capacity = P
50

(0.5)
1/2
The heat capacity is constant, regardless of how the transformer is to be used. Since the
heat capacity will be the same even when the transformer is used with maximum input
P
max
, it follows that the duty factor will be restricted by a certain value, and this value will
be called the "allowable duty factor"

max
. That is, they will have the following
relationship.
P
50

(0.5)
1/2
= P
max

(

max
)
1/2
In other words, the duty factor will have to be reduced when the welding machine or
welding transformer is to be used with a large input kVA, and when using it with the duty
factor increased, it will exceed the heat capacity of the welding transformer unless the
input kVA is lowered. This can easily be examined, if you apply values to
above-mentioned formula.