troubleshooting refrgerator

[Kirk Leach]

Hello,

I live in Latin America and am having a problem with refrigeration in
my house that I think must be related to the electrical supply.

The refrigerator works properly for a period of time, several days,
and then does not, for several days at a time, with the temperatures
going into the 50s. Obviously unacceptable. We have tried six
different refriegerators, and it is happening with them all, so we
highly doubt the problem is the refrigerator.

We have had the electricity checked by three different electricians
and all get 110V from the socket, even when the fridge is not working
properly. They have check various other things, to no avail.

I have never had this kind of problem before, and that includes living
in Latin America for several years.

Anyone have any ideas what could be going on?

Thanks!

 

[Jack Hayes]

Hello,

I live in Latin America and am having a problem with refrigeration in
my house that I think must be related to the electrical supply.

The refrigerator works properly for a period of time, several days,
and then does not, for several days at a time, with the temperatures
going into the 50s. Obviously unacceptable. We have tried six
different refriegerators, and it is happening with them all, so we
highly doubt the problem is the refrigerator.

We have had the electricity checked by three different electricians
and all get 110V from the socket, even when the fridge is not working
properly. They have check various other things, to no avail.

I have never had this kind of problem before, and that includes living
in Latin America for several years.

Anyone have any ideas what could be going on?

Thanks!

Any chance it is running way off frequency?

Jack

 

[John Fields]

Hello,

I live in Latin America and am having a problem with refrigeration in
my house that I think must be related to the electrical supply.

The refrigerator works properly for a period of time, several days,
and then does not, for several days at a time, with the temperatures
going into the 50s. Obviously unacceptable. We have tried six
different refriegerators, and it is happening with them all, so we
highly doubt the problem is the refrigerator.

We have had the electricity checked by three different electricians
and all get 110V from the socket, even when the fridge is not working
properly. They have check various other things, to no avail.

I have never had this kind of problem before, and that includes living
in Latin America for several years.

Anyone have any ideas what could be going on?

---
It sounds like you may be getting an intermittent or a high-resistance
connection at the breaker panel or perhaps in the socket the
refrigerator is plugged into. If the electricians unplugged the
refrigerator and then measured the voltage at the socket that could
give them the 110V reading they got because there'd be no appreciable
load and therefore no appreciable voltage drop across the
socket/breaker. Since the fridge sometimes works and sometimes
doesn't, what I'd do to isolate the problem even further would be to
run the fridge from an outlet fed by another breaker for a while and
see what happens. If it runs with no problems for say, a couple of
weeks, then I'd start checking the wiring.

 

[Kirk Leach]

Any chance it is running way off frequency?

Jack

I am not sure what that means. Please clarify.

 

[Rich Grise]

I am not sure what that means. Please clarify.

Apologies if this is insultingly basic, but you never know:

Power lines are AC, alternating current. The frequency is the rate at
which the current "turns around".

Many motors, called induction motors, derive their operating speed
from that frequency, because the AC sets up a rotating magnetic
field in the motor, which then drags the armature around behind
itself. (the magnetic field does this dragging). Getting a magnetic
field to rotate is a different topic - call it electronics trickery
for now.

If the line frequency is too low, the motor won't get up to
the proper speed, and won't generate proper back EMF, so it will
overheat and trip the thermal cutout.

If the frequency is too high, the motor might simply not run
at all because the rotor can't keep up.

Next time you ask the power company to look at your mains,
ask them if they have a recording frequency meter as well as
voltmeter and spikemeter and all that.

Good Luck!
Rich