TV capacitor instead of motor capacitor

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    Capacitor Motor
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Discussion Overview

The discussion centers on the feasibility of using an old TV capacitor as a replacement for a failed motor capacitor in a 1 hp farm motor running on 220 AC. Participants explore the differences between motor capacitors and TV capacitors, particularly in terms of their electrical characteristics and safety implications.

Discussion Character

  • Debate/contested
  • Technical explanation

Main Points Raised

  • Some participants assert that motor capacitors are bi-polar AC components, while TV capacitors are typically DC, suggesting that using a TV capacitor could be inappropriate.
  • One participant emphasizes the importance of using the correct replacement part to avoid future failures and additional costs.
  • Another participant questions the motivation behind seeking a shortcut, implying concerns about the motor's condition and the willingness to invest in the correct part.
  • Some participants highlight the potential dangers of using a DC capacitor in an AC application, noting that it could lead to catastrophic failure.
  • A later reply provides a technical explanation regarding the construction of electrolytic capacitors and the risks associated with incorrect usage.

Areas of Agreement / Disagreement

Participants generally disagree on the appropriateness of using a TV capacitor as a replacement for a motor capacitor, with some strongly advising against it due to safety concerns, while others express uncertainty about the differences and potential outcomes.

Contextual Notes

There are unresolved questions about the specific requirements for the motor capacitor, such as its voltage rating and whether it is a start or run capacitor. The discussion also reflects varying levels of understanding regarding capacitor types and their applications.

John1397
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TL;DR
Have farm motor 1 hp 600 mf capacitor failed can one slip old tv style capacitor in old can as this motor runs on 220 ac?
Have farm motor 1 hp 600 mf capacitor failed can one slip old tv style capacitor in old can as this motor runs on 220 ac?
 

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Probably not.
A new cap shouldn't be more than $20 US, although that is a pretty large mfd.
 
John1397 said:
Have farm motor 1 hp 600 mf capacitor failed can one slip old tv style capacitor in old can as this motor runs on 220 ac?
NO. The motor capacitors are Bi-polar AC, not DC like those used in electronics.
How many capacitors does it have?
Is the AC capacitor rated at 250 VAC for starting, or 450 VAC as a run capacitor ?

If it has only one, a start capacitor, then it needs a value somewhere between 30 uF and 60 uF.
Motor start caps are available from electrical providers and on the web.

The unit uF = 1x10-6, once used to be called mmF, = 1x10-3 * 1x10-3 = 1x10-6 = uF.
 
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Get the correct replacement part. The cost of future failures and repeated repairs is more significant than the cost of the correct part. You'll probably end up buying it eventually anyway.
 
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John1397 said:
Have farm motor 1 hp 600 mf capacitor failed can one slip old tv style capacitor in old can as this motor runs on 220 ac?
Instead the bottom of the capacitors please add some pictures about the text on the sides.
Also, something about the motor so we can identify it.

If it remains a guesswork as it is right now, then the general answer is - no.
 
Motor starting capacitors really can't be replaced with anything else. Why are you wanting to take this shortcut? Are you concerned the motor is defective and don't want to waste the money on the correct part?
 
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Only difference I see and don't understand is motor capacitor is AC and tv capacitor is DC, see no reason to not try either motor will start or not.
 

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It is all to do with the chemistry at the surface of the aluminium foil.
From: https://en.wikipedia.org/wiki/Electrolytic_capacitor
"Electrolytic capacitors are polarized components due to their asymmetrical construction and must be operated with a higher voltage (ie, more positive) on the anode than on the cathode at all times. For this reason the anode terminal is marked with a plus sign and the cathode with a minus sign. Applying a reverse polarity voltage, or a voltage exceeding the maximum rated working voltage of as little as 1 or 1.5 volts, can destroy the dielectric and thus the capacitor. The failure of electrolytic capacitors can be hazardous, resulting in an explosion or fire. Bipolar electrolytic capacitors which may be operated with either polarity are also made, using special constructions with two anodes connected in series. A Bipolar electrolytic capacitor can also be made by connecting two normal electrolytic capacitors anode to anode or cathode to cathode."
 
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John1397 said:
motor capacitor is AC and tv capacitor is DC
DC caps cannot handle AC. It'll just explode.
And it'll be quite violent too. Just don't do do this.
 
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@John1397 is apparently not listening to our good advice, and is intent on trying dangerous (and stupid, IMO) stuff. This thread is closed.
 
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