E
Eric R Snow
- Jan 1, 1970
- 0
Greetungs All,
I have a small generator (700 watt, 850 surge) that I use to keep the
fridge running when the power is out. It is a robust unit made by
Robin and is at least 20 years old. It has an accurate analog
voltmeter on it. I tested it by comparing to a digital meter and by
directly connecting just the meter to the 115 volt, 60 Hz mains. The
label says that the generator puts out 60 Hz but when checked with an
oscilloscope (TEK 465B) it shows about 50 Hz. Even though the fridge
seems to run fine it sounds different than when operating from the
mains. The meter on it shows the voltage as being 115 volts and the
motor is running at the nameplate RPM. So what could be the reason for
the 'scope showing the lower Hz and is there anything I can do about
it? This generator uses brushes on a slip ring to energize the field
winding and has some type of transistorised voltage regulator.
Thanks,
Eric R Snow
I have a small generator (700 watt, 850 surge) that I use to keep the
fridge running when the power is out. It is a robust unit made by
Robin and is at least 20 years old. It has an accurate analog
voltmeter on it. I tested it by comparing to a digital meter and by
directly connecting just the meter to the 115 volt, 60 Hz mains. The
label says that the generator puts out 60 Hz but when checked with an
oscilloscope (TEK 465B) it shows about 50 Hz. Even though the fridge
seems to run fine it sounds different than when operating from the
mains. The meter on it shows the voltage as being 115 volts and the
motor is running at the nameplate RPM. So what could be the reason for
the 'scope showing the lower Hz and is there anything I can do about
it? This generator uses brushes on a slip ring to energize the field
winding and has some type of transistorised voltage regulator.
Thanks,
Eric R Snow