yyddzb
第61楼2011/12/26
恩,受教了,可能岛津的是这样吧!多多讨论,多多学习,只是希望稍微说专业一点,灯丝可以作为收集极来使用,其他品牌的可能不是。
dbzxh
第64楼2011/12/26
你有实际的电路图吗?我想查一下我们的灯丝1不能点亮的问题. 我的qq:417222365
dbzxh
第67楼2011/12/27
3. Checking the filament currents
When a filament is on, the filament current can be determined from the following voltage
measurements. The relationship between the filament current and the voltage measured
with the tester + probe on CP16[FIL] and the - probe on CP18[EV] is as follows:
Filament current (A) = 2 x (VCP16 – VCP18) max about 3.5A
If (VCP16 – VCP18) = 1.4V, the filament current is 2.8A.
A filament discontinuity is detected and an error occurs if (VCP16 – VCP18)≤approx. 0.6V, that
is if the filament current ≤approx. 1.2A.
The discontinuity in the filament can be easily confirmed by the following method.
Turn off the filament and measure the resistance between F1+ and F1-.
If resistance value ≤1Ω, the filament is normal.
Be aware of the polarity when measuring the resistance; correct measurement is only
possible by applying a positive voltage to F1+ and a negative voltage to F1-. If the polarity
is unknown, turn off the instrument power, remove IS CTRL-A to eliminate the influence of its
circuits and measure the resistance directly at the feedthrough terminals.
4. Checking the TRAP current control circuit
Set the emission current, turn the filament on, and measure the voltages at CP12[EMC],
CP13[TRP], and CP14[+10A].
If VCP14≠10V, the IS CTRL-A PCB is probably defective.
VCP12=set current(μA)/100
If emission current = 60μA, VCP12=0.6V.
Any abnormality suggests an incorrect D/A voltage from the CPU PCB.
VCP12=VCP13
Any abnormality could be due to a filament discontinuity or incorrect installation.
5. Checking the emission voltage control circuit
This circuit generates the emission voltage (-10V to -200V).
Set the emission voltage, turn the filament on, and measure the voltages at CP15[EMV],
CP18[EV], and CP19[INV].
VCP15= 0.05 x set voltage (V)
If emission voltage = -70V, VCP15=-3.5V.
Any abnormality suggests an incorrect D/A voltage from the CPU PCB.
VCP18= set voltage (V)
A voltage in the range set voltage ±10% is normal. If abnormal, check the voltage VCP19.
If VCP19 is not in the range +1 to +15V, the IS CTRL PCB is probably defective.
If the VCP19 voltage is in the normal range but VCP18 ≠set voltage, the filament wiring is
probably touching another electrode inside the vacuum vessel.
这些就是有关灯丝的内容,过几天不忙了,检查一下我们的灯丝1为什么不能点亮的原因。