SLAA898 September 2022 TAS3251 , TPA3255
Another important transformer parameter is the DC resistance of the primary and secondary sides. It can be used to estimate the copper loss in the winding. DCR is obtained by directly measuring two taps with the other side open (without any load).
For step-up transformer 1, the DCR is as listed in Table 3-4.
Side | Taps | DCR (Ω) |
---|---|---|
Primary (common tap: tap 1) | 1,2 | 0.143 |
1,3 | 0.154 | |
1,4 | 0.18 | |
1,5 | 0.26 | |
Secondary (common tap: tap A) | A,B | 0.42 |
A,C | 0.69 |
For step-up transformer 2, the DCR is as listed in Table 3-5.
Side | Taps | DCR (Ω) |
---|---|---|
Primary (common tap: Wht) | Wht, 4 Ω | 0.2 |
Wht, 8 Ω | 0.36 | |
Primary (common tap: Blk) | Blk, 70 V | 0.53 |
Blk, 100 V | 0.96 |
For step down transformer, DCR is as listed in Table 3-6.
Side | Taps | DCR (Ω) |
---|---|---|
Primary (common tap: PRI Blk) | PRI Blk, 10 W | 27.7 |
PRI Blk, 5 W | 54.4 | |
PRI Blk, 2.5 W | 87.7 | |
PRI Blk, 1.25 W | 141.2 | |
PRI Blk, 0.62 W | 221.2 | |
Secondary (common tap: SEC Blk) | SEC Blk 4 Ω | 0.54 |
SEC Blk 8 Ω | 0.72 |