Door-bell transformers have an excuse to be sloppy. The normal load is uncritical and intermittent. However it could be shorted indefinitely. Mine didn't work because it had bare splices laying on the steam pipes. They aren't allow to catch fire when that happens. And fusing is not a good option: doorbell wiring is figured-out by trial and error, with a lot of dead-short errors. So they build in lots of dead resistance, and adjust the turns ratio to give the right voltage at nominal load. No-load, it rises higher, but not to any dangerous voltage.
+- power supply
- Thread starter dharma one
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