Unitek UNIBOND 2, User Manual

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8 . 0 7 . 0 7 . When t h e Pulse Amplitude i s changed t o any v a l u e between 1 . 0 0 and 1 . 9 9
v o l t s , t h e p u l s e amplitude o f t h e d i s p l a y should b e w i t h i n 0 . 0 6 v o l t s o f t h e
amplitude s e l e c t e d .
8 . 0 7 . 0 8 . When t h e Pulse Amplitude i s changed t o any v a l u e between 2 . 0 0 and 3 . 9 9
v o l t s , t h e p u l s e amplitude o f t h e d i s p l a y should b e w i t h i n 0 . 1 2 v o l t s o f t h e
amplitude s e l e c t e d .
8.08. C H E C K THE OVERLOAD INDICATOR
8.08.01. T h e Overload C i r c u i t i s intended t o discontinue t h e Output Pulse i n case one
of t h e f o l l o w i n g occurs:
a. T h e Unibond i s t r i g g e r e d b e f o r e t h e Output Transformer c o r e has r e -
covered from t h e l a s t p u l s e .
b. T h e output c u r r e n t exceeds 1000 amps.
c. T h e output t r a n s i s t o r s a r e o p e r a t i n g i n an unsafe operating a r e a .
Such a n occurrence w i l l be i n d i c a t e d b y t h e absence o f a "beep" f o l l o w i n g t h e weld,
and t h e Overload I n d i c a t o r should l i g h t . T h e I n d i c a t o r w i l l remain l i t u n t i l a p u l s e
i s f i r e d which does n o t cause a n overload.
8 . 0 8 . 0 2 . Connect a 5 m i l l i o h m l o a d across t h e output t e r m i n a l s o f t h e Unibond Output
Transformer. S e t t h e Pulse Amplitude t o 0 . 9 9 v o l t s and t h e Pulse Duration t o 7 9 ms.
F i r e t h e Unibond. A "beep" should b e heard and t h e Overload I n d i c a t o r should remain
OFF.
8 . 0 8 . 0 3 . Now, f i r e t h e Unibond, and f i r e i t a g a i n w i t h i n 1 second. T h e second p u l s e
should n o t b e completed, a s evidenced b y t h e absence o f a "beep." T h e Overload I n -
dicator should be ON.
8.09. C A L I B R AT I N G THE MODEL UBM METER ACCESSORY
8.09.01. Connect t h e Meter t o i t s r e c e p t a c l e on t h e r e a r o f t h e Unibond. I n s e r t t h e
the 10 m i l l i o h m l o a d provided w i t h t h e UBM i n t o t h e Electrode Holders o f t h e Weld
Head.
8.09.02. V e r i f y t h a t i t c o r r e c t l y reads 1 0 milliohms and sounds i t s a u d i b l e alarm
when t h e Push- t o -Read Button i s pressed o n t h e r e a r o f t h e Unibond.
8 . 0 9 . 0 3 . I f t h e Meter does n o t r e a d a n d / o r operate p r o p e r l y, s w i t c h power OFF and
remove i t s c o v e r.
8 . 0 9 . 0 4 . S e t t h e Unibond I I c o n t r o l s a s f o l l o w s :
AMPLITUDE 1 . 0 0 v o l t s
DURATION 5 milliseconds
WELD RESISTANCE CONTROL 5 milliohms
WELD RESISTANCE SWITCH X 1
8 . 0 9 . 0 5 . Mechanically r e z e r o t h e Meter, i f necessary. A d j u s t R 1 , t h e 1 KHz D r i v e
Potentiometer, u n t i l t h e Meter reads 1 0 . 0 milliohms. R 1 i s accessible through t h e
side cover o f t h e Meter o n Stock No. 1 0 - 2 6 6 - 0 2 .
8 . 0 9 . 0 6 . R e p l a c e t h e Meter Cover.
- 2 9 -