Test |
Description |
Main Application |
Winding Tested |
Reason for Test |
CTY |
Continuity |
All transformers |
� |
Properly installed fixture |
R |
DC Resistance |
All transformers |
All windings |
Properly installed fixture
Correct wire used
Integrity of terminations |
LS |
Inductance
(Series circuit) |
Most transformers
But usually not line frequency
transformers |
One winding usually the
primary |
Correct primary turns
Right grade of core material
Core correctly assembled |
LP |
Inductance
(Parallel circuit) |
QL |
Quality Factor |
� |
RLS |
Equivalent Series
Resistance |
Right grade of core material
Core correctly assembled
Check for shorted turns |
RLP |
Equivalent Parallel
Resistance |
D |
Dissipation Factor |
LL |
Leakage Inductance |
SMPS transformers
Communication transformers
Others as applicable |
Selected windings |
Check windings have been
installed in the correct position
relative to the core |
LLO |
C |
Interwinding Capacitance |
High frequency transformers
Isolating transformers |
� |
Check winding positioning Check
insulation thickness between
windings |
TR |
Turns Ratio and Phasing |
Most transformers, but usually
not line frequency
transformers |
All windings |
Check windings have correct
turns and phasing |
TRL |
Turns Ratio by
Inductance |
As with Turns Ratio but used
where there is poor flux
linkage between windings. |
All windings |
Check windings have correct
turns and phasing |
MAGI |
Magnetising Current |
Usually line frequency
transformers |
One winding, usually the
primary |
Correct primary turns
Correct core material properly
assembled |
MAGX |
MAGI (External Source) |
VOC |
Open Circuit Voltage |
All other windings |
Correct secondary turns
Correct phasing |
VOCX |
VOCX (External Source) |
LVOC |
Low Voltage Open Circuit |
IR |
Insulation Resistance |
All transformers |
Between selected windings |
Winding isolation check where
safety is not involved |
HPDC |
Hi-Pot (DC) |
All transformers especially
those used for safety
insulation |
Between selected windings
usually primary to secondary,
screens and core |
High voltage safety insulation |
HPAC |
Hi-Pot (AC) |
LSB |
Inductance with Bias
Current (Series Circuit) |
Transformers for use in
applications where passing
significant (dc) bias current is
part of the normal operation |
One winding |
Correct number of turns
Right grade of core material
Core correctly assembled |
LPB |
Inductance with Bias
Current (Parallel Circuit) |
WATT |
Wattage |
50Hz Iron core transformers |
One winding |
Correct core material
Properly assembled |
WATX |
WATT (External Source) |
SURG |
Surge Stress Test |
All transformers, especially
those using fine wire |
Selected windings |
To identify shorted turns |
TRIM |
Trimming Adjustment |
Transformers with variable /
trimmable components |
� |
To adjust transformer to give
specific measured values |
OUT |
Output To User Port |
� |
� |
Allows the AT to perform external
switching as part of the test program. |
R2 |
DC Resistance Match |
SMPS, audio & telecom |
All windings |
Checks matching between windings |
L2 |
Inductance Match |
SMPS, audio & telecom
transformers |
All windings |
Checks matching between windings |
C2 |
Capacitance Match |
SMPS, audio & telecom
transformers |
All windings |
Checks correct winding position
on bobbin |
GBAL |
General Longitudinal
Balance |
Audio & telecom transformers |
Selected Windings |
Checks common mode rejection
ratio |
LBAL |
Longitudinal Balance |
Audio & telecom transformers |
Selected Windings |
Checks common mode rejection
ratio |
ILOS |
Insertion Loss |
Audio & telecom transformers |
Selected Windings |
Checks losses within the
transformer |
RESP |
Frequency Response |
Audio & telecom transformers |
Selected Windings |
Checks losses over a range of
frequencies |
RLOS |
Return Loss |
Audio & telecom transformers |
Selected Windings |
Checks losses returned by a
transformer |
Z |
Impedance |
Audio & telecom transformers |
Selected Windings |
Checks impedance at a given
frequency |
ZB |
Impedance + bias |
Audio & telecom transformers |
Selected Windings |
Checks impedance at a given
frequency |
STRW |
Stress Wattage |
Line frequency & High
Frequency Transformers |
One Winding (Usually the
primary) |
Checks integrity of inter-turn
insulation, the magnetic material
and joints |
STRX |
STRW (External Source) |
ANGL |
Impedance Phase Angle |
Audio & telecom transformers |
Selected Windings |
Finds phase shift between
Voltage and Current on a winding. |
PHAS |
Interwinding Phase Test |
Audio & telecom transformers |
Selected Windings |
Measures phase shift between a
pair of windings |
ILK |
Leakage Current Test |
Medical applications |
Between Primary and
Secondary Windings |
Checks for a common mode
current due to capacitance |
LSBX* |
Inductance with External
Bias (Series Circuit) |
Wound components that
usually carry a significant DC
Bias current in normal
operation. |
Selected Windings |
Checks number of turns, right
grade of correctly assembled core
material, where bias current is
greater than LSB test can handle. |
LPBX* |
Inductance with External
Bias (Parallel Circuit) |
Wound components that
usually carry a significant DC
Bias current in normal
operation. |
Select Windings |
Checks number of turns, right
grade of correctly assembled core
material, where bias current is
greater than LPB test can handle. |
ZBX* |
Impedance with External
Bias |
Audio & Telecom |
Select Windings |
Checks impedance at a given
frequency, while applying a
greater bias current than is
possible with ZB test. |
ACRT |
Hi-Pot Ramp (AC) |
All transformers especially
those used for safety
insulation |
Between selected windings
usually primary to secondary,
screens and core |
High voltage safety insulation |
DCRT |
Hi-Pot Ramp (DC) |
ACVB |
Voltage Breakdown (AC) |
Transformers with MOV fitted |
Between selected windings
usually primary to secondary,
screens and core |
High voltage safety insulation |
DCVB |
Voltage Breakdown (DC) |