Paradise Energy offers valuable resources for your solar journey. 👇 📙 Download your solar buyer's guide (3,500+ downloads): bit.ly/3uwMtsb 💻 Calculate your solar cost and savings: bit.ly/42HK7TV 🔋 Calculate your battery system size and cost: bit.ly/3uGrS4w 🎓 Get answers to all your solar questions: bit.ly/3UMUV1f
So this shows a possible fault in testing results. We constantly have fluctuating water levels in our pipes, no matter what we do to try to keep it out. So this is absolutely a real possibility. Im actually looking into how to find the fault/nick/comprised insulation in a service wire inside burried pvc. Ws used a spit fire which works like a meghor but it sends a pulse which then can detect a fault on the surface by probes. We decided to run a new wire. But I'd like to find other testing options to get us right on top of the issue more efficiently.
Thank you I need to show this to my superintendent. They wanted our cables megged that are in a cablebus but if something got nicked while pulling, unless the bad spot is still touching the tray, the megger doesn't show.. They told me to hook the positive to the cable, negative to a completely separate ground wire..
This test is very realistic. Is the rule of thumb 1 Megaohm for every 1000 V, but at least 1 Megaohm still up to date? A value under 2 Megaohms is always critical.
The test we shared is a very simple insulation resistance test meant to show how an obvious fault may not be found unless there is a way for fault current to flow from the damaged conductor to the conduit or an adjacent damaged conductor. We don't test above 1000V, as our test is a very basic test. Any result less than one megaohm will cause us to further evaluate the conductor. We would encourage anyone interested in doing more advanced testing or testing at higher voltages to consult the equipment manufacturer for their instructions on how to properly use their instrument at higher voltages and how to interpret the test results. We don't make any claims to have an expert level of insulation resistance testing experience, and are always glad to hear from those with more experience than what we have! Thank you for the feedback.
The purpose of the video is to share that an insulation resistance test may not give the user an accurate indication of an insulation fault under circumstances where the exposed conductor isn't touching another exposed conductor or metal conduit. The purpose of introducing water in the video is to demonstrate the concept. We don't have the technical expertise to guide you on the safety of using an electrically conductive gas. Please seek qualified guidance, as many gases can be explosive under the right conditions, and we want to avoid this!
Question would performing this test cause the conduit to be energized momentarily if say i test the line wire in respect to ground or nuetral to ground or line/ neutral to ground?
Insulation resistance testing should be performed by qualified and trained personnel. The test involves using a calibrated insulation resistance test meter. We use a meter from a company called Megger. All conductors being tested must be de-energized and locked out from potential energy sources using approved Lock Out Tag Out procedures. Conductors should be removed from terminals according to the meter test instructions. The test does involve connecting the positive and negative probes of the meter to the conductor being tested, and to the metal conduit, other conductor, equipment grounding conductor, or neutral conductor. A voltage is introduced on to the test conductor. If there is an insulation fault, the amount of resistance between the test conductor and other conductor, metal conduit, etc, is measured. If the meter detects too low of a resistance, it will stop the test. However, depending on the amount of resistance the meter measures, there could be momentary voltage on the metal conduit. The person conducting the test must wear appropriate Personal Protective Equipment, such as tested insulated gloves and safety glasses, and must ensure that all other people are aware of the test and are not touching any surfaces that could conduct test voltage. All conductors that are not landed on terminals must be capped with a properly rated insulating cap or tape. Again, the test should be conducted by properly trained personnel who are aware of the proper safety procedures to follow during the test.
If you're located in the mid-Atlantic region and have a PV solar system that needs maintenance, our team of solar energy experts is ready to help. Learn more about our maintenance services and contact our team here: bit.ly/3hfqs6Y
