Can you change a 50 microfarad capacitor rated at 370 volts with one rated at 440 volts?

Answer 1

Field replacement of a capacitor when you don't have the correct size available.

It is an acceptable temporary fix to go up one rating size (for example, from a 5 microfarad original up to a 7.5 microfarad replacement) so long as the voltage of the replacement capacitor is equal to or greater than the original and the current draw under load does not exceed the appliance's current rating as stated on its rating plate.

It is important to stress that a capacitor of the correct size should be installed as soon as possible because a larger capacitor will allow a higher current to flow. (Larger meaning not the outside dimensions physically but the capacity in microfarads.) Assuming the supply voltage, supply frequency and everything else in the circuit stays the same, it is safest to assume that the current will increase directly in proportion to the increase in the microfarad capacity. So adding 50% more microfarads would result in 50% more current. If there is a transformer or a motor in the circuit the extra current could damage its windings or even cause a fire!

So be careful! IF YOU ARE NOT ALREADY SURE YOU CAN DO THIS JOB

SAFELY AND COMPETENTLY

REFER THIS WORK TO QUALIFIED PROFESSIONALS.

If you do this work yourself, always turn off the power

at the breaker box/fuse panel BEFORE you attempt to do any work AND

always use an electrician's test meter having metal-tipped probes

(not a simple proximity voltage indicator)

to insure the circuit is, in fact, de-energized.

Answer 2

It seems like you are replacing a microwave oven capacitor. Usually +_ 10% is OK, so in this case it should be OK. That is a correct answer: you can replace the capacitor as long as you are within +/- 10% of the original microfarads of the original capacitor

Answer 3

In general yes, as long as the 33 uF cap being replaced and replacing are both directional/nondirection. You're talking about replacing with a MUCH bigger cap, so space constraints may prevent this.

Answer 4

You can switch a 50 volt capacitor with one rated for 85 volts. Switching a 220 microfarad capacitor, however, with one rated at 2200 microfarads is not a good idea. Yes, the larger capacitance will give you more filtering, but it will also increase the inrush time on the rectifier diodes as well as increase the average power dissipation in the following stage regulator.

Answer 5

In many cases, yes, for example in smoothing or decoupling, but sometimes the capacitance is used to define a timing circuit or the frequency response of a filter, then the right capacitance must be used.

Answer 6

You should be able to switch these capacitors since there is a safe region of the tolerance factor that stays within + or - 20% of most capacitors. Great care must be taken in dropping to lower voltages in the selection of a capacitor. At this rating of such a high voltage the difference in voltage is 100 volts. This should not matter too much because of such high voltage range. However this much voltage difference would matter in lower voltage circuits and the capacitor may overheat. This is still an acceptable switch and should operate within these circuit parameters.

Answer 7

Using a higher voltage cap than the original is OK, using a lower voltage one is not.

If you do it, it may work for a short while - and then explode!

Answer 8

A: No problem there the idea is to change to a higher voltage rated capacitor to improve reliability however do not try the other way around poof

Answer 9

Yes you can, the voltage is the main limitation for a capacitor. But 5 uF might not have the same effect as 7.5 uF, it depends on the application.

Answer 10

You've not stated which is the original, and which is the replacement.

Answer: maybe, maybe not. It depends on the circuit, and whether the replacment is to be larger or smaller.