APX 525/625 Generator Revision C Service Adjustments
©
2005 Del Medical Imaging Corporation
7/5/2005 Page 133
during exposures, as dangerously high voltage can be present when there are
improper connections.
mAs measurements may also be made using the storage oscilloscope and
calculating mAs as a product of tube current and time, as measured using the mA
waveform.
Del Medical Imaging Corporation tests all systems for mAs, kV, and mA accuracy,
using Dynalyzer™’s equipped with digital displays.
Instructions for performing field calibration of the APX 525/625 generator, when no
Dynalyzer™ is available, may be found in this section Alternate Calibration
Procedure.
Oscilloscope connections to the Dynalyzer™ for mA waveform measurements
should be made at the BNC terminal marked “mA”. The mode switch on the
Dynalyzer™ should be set to “RAD”. The output of the Dynalyzer™ is scaled to 1
millivolt per mA, or 100mV per 100 mA, with the oscilloscope set to the 1X setting for
the scope probe input.
During normal exposures, the generator may induce irregular patterns of low voltage
noise spikes, which may be picked up in the coax between the scope and the
Dynalyzer™ and displayed as a component on the mA waveform. This is due to the
high sensitivity of the oscilloscope input at such a low voltage scale, and does not
necessarily indicate a performance problem in the generator.
Dynalyzer / Scope Setup
1. Connect Channel 1 of the scope to "A + C" BNC output of the Dynalyzer™
2. Connect Channel 2 of the scope to the "mA" BNC output of the Dynalyzer™
3. Set scope as follows:
Ch. 1 Vertical Scale
2 V / Division
Ch. 2 Vertical Scale
100 mV / Division
Horiz. Scale
10 mSec / Division
Display Mode
Chop
Trigger
Channel 1
Polarity
Positive
To Next Page
Loading...