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What source can I read about safe procedure for testing circuit breaker?

What source can I read about safe procedure for testing circuit breaker?

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  #1  
Old 12-26-18, 03:01 PM
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What source can I read about safe procedure for testing circuit breaker?

You guys know I am a cautious person from my posts. Would anyone feel comfortable telling me the procedure for testing my double-pole water heater circuit breaker with my multi-meter? I've done some reading online. But I just want to make sure. If you don't want to go into this, can you tell me a good source to learn about this online?
 

Last edited by bluesbreaker; 12-26-18 at 04:54 PM.
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Old 12-26-18, 03:19 PM
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How do you mean..... check it ?
Making sure it's putting out 240vAc ?
Set your meter to the scale over 240vAC. Put one probe on each of the screw terminals.
There is really no homeowner way of testing it for correct trip current.
 
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Old 12-26-18, 04:30 PM
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Electrical fires are more likely caused by loose connections that heat up with far fewer amperes flowing than needed to trip the breaker, compared with an overload (too many amperes).

You can feel the surface of the breaker form the front of the panel to find overheating due to a loose connection inside the breaker.

Measure the voltage across the feed wires just after they enter the water heater with the water heater kicked on and also across the breaker terminals with the water heater kicked on. A difference of more than two percent will reveal a possible loose connection in the wiring back to the panel.
 
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Old 12-26-18, 05:02 PM
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Correct.....................to see if it is putting out 240 Volts. I don't know where to touch red and black multi-meter probes on the circuit breaker.
 
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Old 12-26-18, 05:41 PM
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Put red probe on either breaker terminal and black probe on the other breaker terminal. Should read about 240V.
 
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Old 12-26-18, 08:10 PM
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...probes on the screws where the wires connect.
 
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Old 12-26-18, 09:02 PM
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Ok. I laid out all the steps for multimeter voltage test of double-pole circuit breaker. I was uncertain of a couple steps which I emboldened with question marks.

Is this correct? Please read this carefully.

-Disconnect twist-on connectors at electrical junction on top of water heater ?

-Main circuit breaker and water heater circuit breakers should both be in the ON position ?

-Wear rubber-soled shoes.

-Make sure there is no moisture on ground below circuit panel

-Unscrew panel supporting panel with one hand.

-Don't make body contact with inside of panel.

-Multi-meter should be set at 750 ACV........red probe plugged in at V(horseshoe)mA............black probe plugged into COM.

-Touch red and black probes to the two screw terminals on breaker. They're interchangeable. The red probe can touch either screw terminal. And the black probe can touch either screw terminal. Reading should be about 240 Volts.

- If you want to test a single pole (on double-pole breaker). Touch red probe to the screw terminal and black probe to any screw terminal on white neutral bar. Single pole test should read about 120 Volts.
 
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Old 12-27-18, 05:16 AM
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Hi, you sure will be safe if you follow the procedure with all the rubber etc. maybe a bit over kill, my question is, is the water heater working correctly?
Geo
 
  #9  
Old 12-27-18, 07:24 AM
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I have a Whirlpool 50 gallon electric water heater model# E50R6-45 100. I don't think it uses a circuit board. I had a hot water failure on Christmas Day. Here are the details.

It currently is not functioning

-Upper thermostat with red ECO button was tripped with burned terminal
-Red and blue wires at right hand second from top terminal were burned and broken.
-Plastic cover melted
-No burn marks on heating element terminals
-No burn marks on lower thermostat terminals
-Circuit breaker not tripped
-Circuit breaker action good and tight. No burn smell
-Also had hot water failure about 12 months ago on same water heater. Replaced elements and Upper T-stat. Function restored.
-I am positive I did not leave any loose wiring. Triple-checked my work
-No burn marks at twist-on connectors at junction box on top of heater.

I know this probably is not a faulty circuit breaker. But I want to test it anyway with the multimeter. My reading seems to indicate that a wiring issue caused this.

I was thinking about replacing the Upper T-Stat and the two burned wires. But one wire extends down the inside wall of the tank from upper T-Stat to the lower element. You can't pull it through either end, Feels like it's stapled to the inside tank wall or something. If I replace the entire wire, it seems it would be difficult to snake it down inside the tank wall. It's still under warranty. But it is discontinued. Huh......I wonder why?
 
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Old 12-27-18, 08:47 AM
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Hi, if it is still under warranty I would start harrassing the mfg.
Geo
 
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Old 12-27-18, 09:27 AM
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Yeah, I'll give the the manufacturer a call before year end. I just want to cover all my bases and also to say I tested my circuit breaker.

I just want to confirm those last two questions about breaker testing.

1. So when I test the breaker, I don't have to disconnect the twist-on wiring at the junction box on top of the water heater?

2. Also when testing the breaker, do I leave both main breaker and water heater breakers in the ON position?

Sorry, don't know much about electricity.
 
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Old 12-27-18, 09:30 AM
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-Upper thermostat with red ECO button was tripped with burned terminal
-Red and blue wires at right hand second from top terminal were burned and broken.
-Plastic cover melted
The red button is a high temperature limit switch and shuts off all power to the unit. Most likely you had loose connections that caused the terminals to burn and heat the thermostat causing the limit switch to trip. The top thermostat needs to be replaced and the burnt wires either repaired or replaced.

The warranty that might cover these items will not be more than one year.
 
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Old 12-27-18, 09:40 AM
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I'm asking for FULL warranty replacement on the entire water tank assembly. It's a poor design. It's so tight in there, you have to grab the wires with pliers to connect to the terminal.
Absolutely no play. My old GE water heater didn't have this problem. If there were loose connections, it's the manufacturer fault because you have to pull the wires to connect. The connections were fine when I did it. Maybe came loose later because wiring was so tight out of the factory. It has a 6 year warranty.
 
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Old 12-27-18, 01:24 PM
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I talked to the store today about making a warranty claim. I would rather wait and do the 'cold shower express' and make an argument for warranty replacement if it comes to that.
 

Last edited by bluesbreaker; 12-27-18 at 01:41 PM.
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Old 12-28-18, 07:02 AM
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Waiting for response from manufacturer and store for warranty claim. I will report back
 
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Old 12-28-18, 07:42 PM
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It has a 6 year warranty.

That's the tank warranty. Good luck, but American Water Heater is the manufacturer. You may have better luck pounding Lowes corporate office with your claim.
 
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Old 12-30-18, 06:11 PM
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I know. The manager at the store told me to contact her if the manufacturer refused.
 
  #18  
Old 12-31-18, 06:55 AM
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I tested the circuit breaker with the multi meter. I got 250 volts on the double pole, and 121 volts on the single poles. I don't know if this meter is reading the double pole correctly. It's just a cheap one I plan to replace. I replaced the battery too.
 
  #19  
Old 12-31-18, 07:02 AM
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Hi, 250 is a bit high but the 121 to Neutral sounds right, probably the meter, is it a digital meter?
Geo
 
  #20  
Old 12-31-18, 09:13 AM
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Two hundred fifty volts is within tolerances for 120/240 volt systems and will not (should not) cause problems with 240 volt appliances.

Also, 121 volts from one hot to neutral, 122 volts from the other hot to neutral, and 250 volts from hot to hot all together mean an inaccuracy in the meter in presenting its readings.
 
  #21  
Old 12-31-18, 12:55 PM
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Yes. Old one is a digital meter. I'm going to buy a new multi-meter after the holiday. So the circuit wasn't the cause of the WH burned wires. But I'll re-test it anyway with a new meter.

I'm looking to use it for home and automotive. I was looking at the Klein 400 amp True RMS one with the clamp. Model# CL310. Will it suit my purposes? Good choice or not?

Also, When I test single poles one at a time (on a double-pole circuit breaker) do I touch the black probe on the same ground terminal screw that the tested breaker is wired too? Or can you touch the black probe to any terminal screw on the long narrow ground strip?
 
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Old 12-31-18, 01:49 PM
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Also, When I test single poles one at a time (on a double-pole circuit breaker) do I touch the black probe on the same ground terminal screw that the tested breaker is wired too? Or can you touch the black probe to any terminal screw on the long narrow ground strip?
All grounds connect to a common point (the ground bus bar) and are therefore electrically at the same potential, so anywhere on that bar will suffice.
 
  #23  
Old 01-01-19, 06:27 AM
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A breaker trips on overcurrent, not over/under voltage. The burnt wires on your water heater was due to some combination of loose terminations, defective t'stat or heating element. The breaker protects the wire (assuming it was sized correctly) from the breaker to the load. The breaker should have a response time such that any short downstream of the water heater breaker resulting in a overcurrent greater than the trip rating of the water heater breaker and the breaker upstream (usually the panel main breaker), the water heater breaker should trip first. This isolates only the water heater, not the whole house.
 
  #24  
Old 01-01-19, 02:31 PM
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Very good. Thanks for the additional info. I'm talking to the manufacturer tomorrow.
 
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Old 01-02-19, 06:16 PM
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How many days of cold showers so far....7?
 
  #26  
Old 01-03-19, 07:17 AM
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Hey Joe, Thanks for asking.

Hope you and the other folks on this site had a nice holiday. Cold showers since the hot water failure on Christmas Day. The manufacturer agreed to a complete warranty replacement. I know how to install the new one myself. But I might have one fact to confirm about the junction receptacle wiring on top of the tank. I'll post a photo late tonight.
 
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Old 01-03-19, 10:09 PM
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I should have a new electric water heater to install this weekend. I just had a question about the electrical junction wiring on the water heater.The photo is from the current defective water heater.

I don't need to splice or weave the black and red wires together do I? They would seem to be a bit heavy for that. I assume I just insert them side by side in the plastic twist-on connector and twist?
 
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Old 01-04-19, 04:35 AM
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Best to twist and use the appropriate wire nut, probably Grey.
Geo
 
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Old 01-04-19, 07:26 AM
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Oh....Ok. I thought those wires might be too thick to twist together. What's the significance of gray twist-on connector? Is it color-coded for size?
 
  #30  
Old 01-04-19, 08:33 AM
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In general the color designate wire size. It varies with manufacturer and can be two sizes for one color.
 
  #31  
Old 01-04-19, 08:53 AM
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That green wirenuts are for ground wire and has a hole in the center to let a wire pass through the hole.
This should not be used.

While color of wirenuts can vary, many follows generic color codes of yellow and red.
Ideal red wire nut or tan color is the size you want. Idea red wirenut is the same size as green ground wirenut you have there. Red wirenut from other manufacturer will about the same size as well.
 
  #32  
Old 01-04-19, 01:16 PM
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Very good. Thanks very much
 
  #33  
Old 01-07-19, 07:24 AM
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I installed the new WH myself and it is up and running now. I started a related thread about color-coded junction wiring. Maybe the two postings should be combined at moderators decision.

I was looking at multi-meters yesterday. I will still check circuit breaker again even though this wasn't likely the cause of the problem. We can close this discussion if you want.
 
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Old 01-07-19, 12:22 PM
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A breaker is not "opened or closed". It is turned on or it is turned off.
If the breaker is turned on then of course voltage is at the wall outlet even if nothing is plugged in to draw current.

A continuity tester tests wires that are not powered, the breaker must be turned off.
 
  #35  
Old 01-07-19, 12:44 PM
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Ok. This is good to know. I am still in the early stages of multi-meter use. So there is some learning to do on my part.
 
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Old 01-08-19, 05:16 AM
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This post has run its course and even got off course many times. Remove it. The OP has a new post continuing the same subjects.
 
 

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