Hobart 5359D Operation And Maintenance Manual page 54

OM 2012
The p 3 we f m 02
'vk IXIWI u~cn?bly (FiJ.
13), sorriztii7-:cs ieefrt4YCd to
C:
the '%oi~ta::t~
pale I I', is lozotod at the right rear of ~IIC machine behind the con:~o! box. On uii
mod, I; e>:cept th, Q tow tractcr mounted unit, it is cccc:: ible by opening right r::tii
clocn .
017 tracts mout~kd
unils it is
ClCCeSS ible by i~Cf?20Vii7g
rfar
CCccss-;*enf.
Ccs;ef (2, Fig. 1) on the cancpy. The pnel assembly provides sensing and OL'.':'-
load p:o:ection
fcr
the
OUtpUt CiiCUit and provides
a freans of connect irtg and dis-
ccnnecting generator outpu, + to and from the load (aiiccaft).
(1) Load contactcz
The load contactor (6, Fig. 13) is a sealed unit which contains a magnetic
operating coil and
fm
sets of contacts. The three larger contacfs conduct
three -phase AC generutor output. A smaller contact set is connected in t-he
protective monitor circuit and suppI ies 12-V DC power used by sen; ing rc !n)~
to signal the protective monitor when a fault occurs. Three-phcie, 400-Hz
generator output power is conducted to the load contactor by 2/O cables which
pass through 3 sets of current transformers (3, 4, and 9).
NOTE: This contacts may.be replaced by the old style contactc~ u;ed
in previous 60-WA mychines.
This nore is fti the benefit of
those users who may have old style contact@s Part number
75GH-566 (Hartman No. A-87&I) in stock.
,
(2) Current trcnzformers
(a) Ammeter current transformers
Three current transformers (4) lower the output load current to a lesser
.valuz of definite ratio (250-A to 5-A) which will operate the ammeter
(4, Fig. 11) movemznt without damage. The a,mrrzter dial scale is
graduated and numbered so that the ammeter pointer will indicate the
true load current value rather than the meter movement current.
(b) Line-drop current transforrrers
The three line-drop current transformers (9), in coniunction with burden
resistors (8), detect the magnitude and power factor of current flowing
from generator to load. They feed a signal to the voltage regulutor
which interprets the signal and alters the exciter field currentas required
to maintain a constant predetermined voltage at the load (see Voltage
Regulator Manual No. TM-232).
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Page 30
Aug 25&i
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