BOC Edwards Temescal SuperSource2 STIH-270-2PT, Руководство пользователя

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6.2 DIF FI CULTIES IN GEN ER ATING OR MAIN TAINING A BEAM
NO. SYMP TOM PROB A BLE CAUSE COR REC TION
1
High volt age is nom i nal, but there is no
emis sion cur rent and no fil a ment cur rent.
(See power sup ply in struc tion man ual for
nom i nal op er at ing val ues.) (a) Fil a ment is bro ken or loose. (a) Using ohm me ter, check con ti nu ity be -
tween fil a ment bus bars. Make sure that
fil a ment legs are prop erly seated in
V-grooves and that the fil a ment clamp
screw is tight.
(b) Re sis tance be tween bus bars is high
be cause of ox ide buildup on fil a ment
clamps. (b) Use ohm me ter to test re sis tance be -
tween bus bars. Read ing should be no
more than 0.3 ohms. If greater, re place fil -
a ment af ter clean ing ox ides from con tact
sur faces (see sec tion 4.2 for in struc tions).
(c) Fault in cir cuit sup ply ing fil a ment cur -
rent. (c) Check the e-beam power sup ply’s gun
con trol cir cuit and the con nec tions be -
tween that cir cuit and the gun.
2
Emis sion cur rent is at max i mum value,
and fil a ment cur rent is nom i nal, but there
is no high volt age. (a) High volt age is shorted to ground. (a) Check for bro ken in su la tors or shorted
emit ter, fil a ment leads, or HV
feedthroughs. Re place parts found to be
de fec tive.
3
No fil a ment cur rent. (a) Fil a ment is bro ken. (a) Check con ti nu ity be tween fil a ment
clamps. If in fi nite re sis tance is in di cated,
fil a ment is bro ken; re place it.
(b) Heavy ox ide buildup on con tact sur -
faces to which fil a ment mounts. (b) Use ohm me ter to check re sis tance be -
tween fil a ment bus bars. If greater than
0.3 ohms, re place fil a ment af ter clean ing
ox ides from con tact sur faces (see sec tion
4.2 for in struc tions).
(c) Fuse F1 on Simba gun con trol board is
blown. (c) Check F1, which is near the board’s
edge con nec tor, and re place as nec es -
sary.
4
Fil a ment burns out when en er gized. (a) Too much fil a ment cur rent is be ing ap -
plied to the fil a ment. (a) Fault in gun con trol cir cuit. Ei ther an
out put tran sis tor or the triac is shorted out.
Check these com po nents and re place
them as nec es sary.
Troubleshooting
6-2 0101-9004-0A STIH-270-2PT