Hitachi H100C, Technical Notes

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Wh en it is n ecessa r y t o r epla ce t h e con t a ct of on e of t h r ee ph a ses, t h e con t a ct s of a ll ph a s es sh ou ld be r epla ced
a t t h e sa m e t im e. N ot e t h a t a ft er r ep la cem en t of con t a ct s, t h e followin g it em s sh ou ld be execu t ed t o ch eck t h e
pr odu ct s.
(1) Measu r e t h e insu la tion r esist an ce bet ween ph a ses, an d bet ween t h e t erm in a ls of power sour ce a nd load t o con firm
t h a t t h e insu lat ion resist a n ce is m or e t h a n 100M
Ω
.
(2) Th e closin g volt a ge sh ou ld be less th a n 85% of t h e r at ed volt a ge of coil.
6-2-3 Ca ut ions in H a ndlin g
It ems wh ich sh ou ld be a voided wh en h a ndlin g t h e swit ch ar e as follows:
(1) Th e wir e t o be con n ect ed t o t h e term in a l shou ld n ot be solder ed.
Th e solder ed w ir es becom e loosen ed w it h t h e pa ss a ge of t im e a n d t h e con t a ct will becom e im per fect , so t h a t
t h ey sh ou ld be a bsolu tely a voided.
(2) Do n ot close t h e win dow of t h e a r c su ppr essin g ch a m ber .
Th e br eak in g perfor m a nce m a y be det er iora t ed.
(3) Do n ot m ou n t on a n a r ea wh ich is less t h a n t h e dim ension s of t he specified m in im um m ou nt in g spa ce.
Th er e a r e possibilit ies t h a t t em per a t u r e r ise m a y in cr ea se a n d gr ou n din g or sh or t circu it m a y t a k e pla ce at th e
t im e of br eak in g. (see pa ge 37)
(4) Do n ot use t h e swit ch wit hou t a n en closur e ou t door s.
Mou n t t h e switch in a pr oper enclosu r e su ch as wa ter-pr oof box, et c.
(5) Avoid m ou nt in g t h e swit ch at a pla ce dir ect ly exposed t o t h e ra ys of t h e su n, a n d a t a h ot pla ce nea r a boiler ,
fu r n a ce, et c. Mou nt in g of t he swit ch a t su ch places m ay ca u se t rou bles su ch as m a lfu n ct ion of t h er m al over loa d
r ela y, bur n t-ou t of oper a t in g coil a n d t he like.
(6) Th e swit ch sh ou ld be pr ot ect ed fr om dir ect splash of wa t er dr ops or oil a n d du st . Pla ce t h e swit ch in a wa t er-
pr oof, dr ip-pr oof a n d dust-pr oof box du r in g use.
(7) Do n ot use t he swit ch wit h out a n en closur e a t a pla ce wh er e t h er e is a con cent r at ion of cor r osive ga s, com bust ible
ga s, sa lt a nd t h e lik e.
(8) Do n ot m ou n t t he swit ch at a pla ce su bject t o a bn orm a l vibr at ion or sh ock.
(9) Do n ot a pply excessive t ensile force t o t h e lea d wir es or t erm in a ls of t he oper a t in g cir cu it a n d t h e m a in cir cu it .
(10) Wit h r espect t o t h e wir e dia met er a nd len gt h of t he oper at in g circu it a nd t h e m a in cir cu it , t heir r esist a nce va lu es
s h ou ld be k ep t below s u ch r esist a n ce va lu es a s m a y im p a ir t h e p er for m a n ce of t h e op er a t in g coil. Im p er fect
closin g of elect r om a gnet will ca use t r ou bles.
(11) Closin g a n d r eleasin g coils of la t ch ed cont a ctor a re r a t ed for a shor t t im e, so t h ey sh ou ld be con n ect ed t o t he
pr otect ion cir cu it wit h ou t fa il, so t h at volt a ge is not cont inu ou sly a pplied.
(12) Do n ot t ur n on a n d off t h e power sou r ce wh en th e in sula t ed cover is open ed.
Th e in su la t ed cover s er ves a s a ba r r ier between ph ases; t h er efor e, if t h e power sou r ce is t u r n ed on or off wh ile
t h e in sula t ed cover is open ed, t h er e is a possibilit y t h a t a sh or t cir cu it between ph a ses m a y t ak e place.
(13) Do n ot use t h e st a r t er for pr ot ect ion a ga in st sh or t cir cu it cu r r en t.
Th e con t a ct or a n d t h er m a l over loa d r ela y ca n on ly wit h st a n d over -cu r r en t of a bou t 10 t im es t h e r a t ed cu r ren t .
U s u a lly, t h e s h or t cir cu it cu r r en t is 10 t o 100 t im es t h e r a t ed cu r r en t , so t h a t t h e con t a ct is m elt ed a n d t he
h ea t er s of t h e t h er m a l over loa d r ela y a r e fused by J ou le h ea t . F or pr ot ect ion a ga in st sh or t cir cu it , F F B or fu se
a r e used.