HF Series Generators
T roubleshooting
TR-1005R4
35
ACTIONS
A. PRELIMINARY
1. Select minimum kVp , minimum mA, and 80 ms (for example 40 kVp, 10mA, and 80 ms). Make
preparation and check that anode rotates in the X-ray Tube. If the anode is not rotating correctly,
check the starter and the Stator connections.
2. In case the anode is rotating correctly, make an exposure:
G If “09” or “Generator Overload” appears follow procedure in paragraph B (Inverter Module
Tes t) .
G If not, follow step-3.
3. Increment kVp in 10 kVp steps, select the same mA and time. Make an exposure:
G If “E09” or “Generator Overload” appears, or the exposure is cut before 80 ms, then follow
procedure in paragraph C (HV Transformer Test).
G If not, keep on increasing the kVp in 10 kVp steps (60, 70, 80, 90, 100, 110, 120 and 125
kVp for 125 kVp HV Transformers; and 130, 140, 150 kVp for 150 kVp HV Transformers)
making Exposures at each kVp selected.
-- If “E09” or “Generator Overload” appears or the exposure is cut before 80 ms at any
kVp selected, follow procedure in paragraph C (HV Transformer Test).
-- If “E09” or “Generator Overload” has not appeared at the maximum kVp or the
exposure was not cut before 80 ms , it means that HV Transformer and HV Cables are
OK. Then follow the procedure in paragraph E. In this case high mA causes E09 or
“Generator Overload”.
B. INVERTER MODULE TEST
1. Power off Generator and mains.
2. Remove the cover from the Generator Cabinet.
3. Wait for the DC Bus of the Inverter to be fully discharged. When it is fully discharged the Leds
on the Charge-Discharge Monitor Board will be completely turned of f.
4. When Leds are off make a jumper between DC-BUS+ and DC--BUS--. Make sure that there is
less than 10 VDC across the BUS. (Refer to Illustration 4-1 to see where to make the jumper).
5. Measure with a Multimeter in Diode (or ohms) between C2E1 (positive polarity) and E2 or C1
(negative polarity) in both IGBTs (refer to Illustration 4-1 for more details). Repeat the measure
with different polarity between C2E1 (negative polarity) and E2 or C1 (positive polarity).
Voltage should be around 0.3 V (or the resistance must be a high impedance) for the IGBT to
be OK. Normally when an IGBT is broken the voltage is = 0 volts (or the resistance is zero Ohms)
or very close.
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