TXR 325D, Руководство по обслуживанию

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M-2008-7-15
Standard Frequency Series Generators
Maintenance 19
Space Charge Transformer
OPEN WINDING.
The Space Charge Secondary winding or terminal connection
including jumpers H1 to H8 maybe OPEN. Use schematic to
test voltage.
Open Filament in X-Ray
Tube.
Select alternate focal spot. Actuate exposures...
If MA is proper on alternate focal spots, tube filament maybe
OPEN.
Shorted Filament in X-Ray
Tube.
To test place volt meter from XC to XS or XC to XL and PREP .
If a short exists your voltage will be 60-70 VAC. This does
not prove the filament in the Tube is shorted unless the
voltage rises above 200 VAC with the Cathode Cable
removed from the X-Ray Tube. If the voltage remains 60
-70 VAC see section under CONDITION SHORTED
OPEN Cathode High Voltage
Cable.
To test Cathode High Voltage Cable, remove from cathode
side of the X-Ray Tube. Place Volt Meter from C to S or C to L
and depress PREP Switch. You should measure 15 -16 VAC.
If you do not measure 15-16 VAC, swap both ends anode and
cathode cables and retest.
Shorted Cathode High
Voltage Cable.
To test Cathode High Voltage Cable for short, place Volt Meter
from XC to XS or XC to XL and PREP. If short exist with
Cathode Cable removed from X-Ray Tube, Proceed. Remove
Cathode Cable from the High Voltage Transformer, and PREP.
If voltage rises to 200 VAC or above the cathode cable is
shorted. Swap Anode and Cathode cables.
LOW MA - NO MA Filament Transformer Output
Shorted.
Remove Cathode Cable from the High Voltage Transformer.
Measurements must be taken inside the Cathode Well on the
Transformer. The Female Docking Groove in the receptacle
is C (Common). Place one probe in the pin aligned with the
Docking Groove and the other on the S or L pin depending on
which focus is selected. Depress PREP and measure voltage.
If 15 - 16 VAC is present filament transformer is OK. If voltage
is not present, check input voltage XC to XS or XC to XL . If
that voltage is 60 -70 VAC then the Ring Terminals on the
Cathode Transformer Well that connects to the output of the
filament transformers are SHORTED TOGETHER. You must
remove Transformer from can and separate the Ring Terminals
attached to the Cathode Well.
Filament Transformer Input
OPEN.
If the filament transformer Primary is suspected to be OPEN,
remove XC , XS , and XL interconnect cable from the High
Voltage Transformer. Measure the resistance from XC to XS
or XC to XL . Resistance should be 20 to 25 OHMS . If OPEN,
remove Transformer from the can and replace ring connectors
or the filament transformer if needed.
kVp Meter read-out on the X-
Ray Control does not match
the Dyanalyzer or ion chamber
reading.
Dyanalyzer or test
instrument defective or out
of calibration.
All TXR Controls are tested and calibrated at the factory.
MA is higher or lower than
selection indicates.
Check and calibrate all MA stations, check space charge. MA
will affect kVp output.
Excessive voltage drop
from power source to X-Ray
Control.
Voltage cannot exceed 5% drop on incoming line to the X-Ray
Control. Either the service transformer is too light duty, wire
sizes are too small or interconnect wire is too long for current
demand.
Voltage Drop caused by
too long of interconnect
cable from X-Ray Control to
Transformer P1 and P2 .
A similar drop in voltage caused by exceeding length and wire
sizes for current demand in the High Voltage Primary Circuit
will have the same results as above. A 5 volt drop will result in
a 6 kVp loss.
KVP Meter Out of
Calibration or Defective
Calibrate kvp meter using load line chart. See kvp meter circuit
theory write-up below.