Fixture Compensation; Fixture - Voltech AT3600 User Manual

V AT3600 U
OLTECH SER
4. F C
IXTURE
AT3600 tester fixture compensation is equivalent to short-circuit and open-circuit
correction on a component analyzer.
components on the fixture board itself. These are usually a combination of parallel
capacitance between adjacent wires and sockets or pins, and series resistance and
inductance along the lengths of wires.
Not all test programs require fixture compensation; and for some programs containing
only high power tests, fixture compensation is not possible. As suggested in Chapter
3, it is best to try fixture compensation when performing trial runs on the program as
it is being developed. If fixture compensation changes the test results, then it should
be applied whenever the program is run in a production situation.
In production test, for optimum accuracy, fixture compensation measurements should
be made :-
1. Whenever the test fixture is changed.
2. At the beginning of each day or work period.
3. Whenever a new test program is loaded into the AT for execution
After you have pressed the COMPENSATE soft-key on the front panel, the tester will
automatically perform all the compensation measurements and retain the results in
internal memory. The compensation factors will then be applied to each transformer
as it is tested.
For compensation, first make up a transformer bobbin with shorting links in place of
the windings:
To make a shorting bobbin, solder short pieces of wire across the relevant pins of an
otherwise blank bobbin. Do not use a bobbin that contains any transformer windings
to make up a compensation test part, since this would invalidate the open circuit
measurements.
Ensure that DC Bias current is switched off before connecting and disconnecting
component under test.
F P O
RONT ANEL PERATION
M
ANUAL
OMPENSATION
Transformer
It eliminates errors due to stray parasitic
Shorting Bobbin for compensation
VPN 98 - 024
F C
IXTURE OMPENSATION
P 6.4.1.
AGE