Safe
I bought a soft heat electric mattress pad. It is supposed to be low voltage and DC. I brought out my portable oscilloscope to check their claims. The power supply says 16 volts on it, and it really is 16 volts. The waveform looked very clean throughout the timescale range of 1 second to 1 microsecond.
After preheat, the unit goes into a pulse width modulation mode of some sort. At a setting of 3, the waveform was high for about 1.3 seconds over a 3 second period.
The pad measured 3.8 ohms after the preheat.
Sunnyvale, CA
Safe
I bought a soft heat electric mattress pad. It is supposed to be low voltage and DC. I brought out my portable oscilloscope to check their claims. The power supply says 16 volts on it, and it really is 16 volts. The waveform looked very clean throughout the timescale range of 1 second to 1 microsecond.
After preheat, the unit goes into a pulse width modulation mode of some sort. At a setting of 3, the waveform was high for about 1.3 seconds over a 3 second period.
The pad measured 3.8 ohms after the preheat.
Sunnyvale, CA