YOKOGAWA WT1800 User Manual page 136

Appendix 5 Setting the Measurement Period
Setting the Synchronization Period When Measuring the
Efficiency of a Power Transformer
• Power Transformer with Single-Phase Input and Single-Phase Output
If you are using input elements 1 and 2 to measure a device that converts single-phase AC
power to single-phase DC power, set the synchronization source of input elements 1 and 2 to
the voltage (or current) on the AC power end. In the example shown in the figure below, set the
synchronization source of input elements 1 and 2 to U1 (or I1).
The measurement periods of input element 1 (input end) and input element 2 (output end) will
match, and it will be possible to measure the power conversion efficiency at the input and output
ends of the power transformer more accurately.
Input: AC power U1 and I1
Likewise, if you are using input elements 1 (DC end) and 2 (AC end) to measure a device that
converts single-phase DC power to single-phase AC power, set the synchronization source of
input elements 1 and 2 to the voltage (or current) on the AC power end (input element 2). In the
example shown in the figure below, set the synchronization source of input elements 1 and 2 to
U2 (or I2).
Input: DC power U1 and I1
• Power Transformer with Single-Phase DC Input and Three-Phase AC Output
If you are using the connections shown on the next page to measure a device that converts
single-phase DC power to three-phase AC power, set the synchronization source of all input
elements to the same signal: the voltage or current of element 2 or 3 on the AC power end.
In this example, set the synchronization source of input elements 1, 2, and 3 to U2 (or I2, U3, or
I3). The measurement periods of the input signal and all output signals will match, and it will be
possible to measure the power conversion efficiency of the power transformer more accurately.
• Single-phase DC power: Connect to input element 1.
• Three-phase AC power: Connect to input elements 2 and 3 using a three-phase, three-wire
system.
App-30
Power transformer
Synchronization Source Setup Example
Input element 1
U1 (or I1)
Input element 2
Power transformer
Synchronization Source Setup Example
Input element 1
U2 (or I2)
Input element 2
Output: DC power U2 and I2
Output: AC power U2 and I2
IM WT1801-03EN