MEGGER MIT515 WITH VOLTAGE FAULT - Page 1
Forum section: electronics / repair

author: HUGOMAN
author_rank: Regular Contributor
timestamp: February 26, 2020, 10:07:36 am
content: Helloi have Megger meghometer mit515, when i apply a test in range 250V it displays only 7 to 10V! please advice about this issue, and it occur the same thing with all voltage ranges.Thanks in advanceRegards

author: shakalnokturn
author_rank: Super Contributor
timestamp: February 26, 2020, 12:39:19 pm
content: This could come from various to things: Measurement section, HV generation, input/output protection.Have you checked the fuse? Has there been battery leakage?Other than displaying a low voltage during isolation tests what resistance does it display on same tests when open and measuring a known resistance such as 100k Ohm?What display do you get when measuring a known voltage?I don't think schematics are available so you may get more help by uploading a few detailed internal photos.

author: HUGOMAN
author_rank: Regular Contributor
timestamp: February 26, 2020, 04:17:29 pm
content: Yes shakalnokturni want to know where the fault comes!1/ i've checked the 2 fuses are ok. plus the smps 220V to 24V ok2/ battery leak---> i measured 12,2V but the connector pins has only 2,2v in each side. i guess the level of battery voltage is up that's why.3/ i put 7W resistor of 100ohms ----> it reads 10,00Kohms with 1volt (very strange)4/ yes sure the known voltage 250V with the load of 100ohm gives 0 to 1volt then without load gives 11 volts in every known voltage range switch.thanks

author: taydin
author_rank: Frequent Contributor
timestamp: February 26, 2020, 05:16:41 pm
content: Before anything else, check to make sure that when you configure an IR test with 250V, with nothing connected to the terminals, that it really does output 250V. If it doesn't then the problem must be in the step up converter.

author: HUGOMAN
author_rank: Regular Contributor
timestamp: February 26, 2020, 08:52:13 pm
content: Thank you Taydin for your response.You have right because there is no voltage at the output olny 11V means that there is a short circuit or what in this stage of step up converter.the problem that i couldn't find in the internet 2days ago any service manual or technical documentation for this mit515 Megger model.

author: shakalnokturn
author_rank: Super Contributor
timestamp: February 26, 2020, 10:38:56 pm
content: Quote from: shakalnokturn on February 26, 2020, 12:39:19 pmShakalnokturn enjoys the autoquote function...I got to see the photos on the other topic, keeping things in one place will get you higher chances of actually finding help.So as said taydin: You could check on one of the lower test voltage ranges and using a dmm what voltage your MIT515 actually generates.One of my previous suggestions was to check the measurement section of your MIT515 using it as a voltmeter to measure anexternalvoltage source.

author: HUGOMAN
author_rank: Regular Contributor
timestamp: February 27, 2020, 10:59:02 pm
content: Thanks to you shakalnokturn and taydin for your help.i have performed today these 2 methodes.1/ the megger mit515 generates only 0,2volts dc; this measured by fluke dmm.2/ the external voltages measurement, it measures up to 1999VAC and VDC too when it exceeds this value no displaying. but the values are incorrect the 100Vof externel source it reads 1500V. so it means that the true 200Vac or DC can not read it.I hope you clarify to me the faulty stage.Regards

author: HUGOMAN
author_rank: Regular Contributor
timestamp: March 07, 2020, 08:01:05 am
content: Can someone help with thi problem; who is no voltage at the output of megger meghometer ?

author: HUGOMAN
author_rank: Regular Contributor
timestamp: March 20, 2020, 07:49:27 pm
content: Unfortenately, i see no contribution for this issue!As you know there no technical data for this instrument available on the internet; by this opprtunity i ask kindly all Eevblog community to share with me how to solve this fault on MIT 515 MEGER.Specially the fault in the output voltage, it is measured is given 0V, and it displays 17V instead of voltage positions switch from 250 to 5KV.Also i noticed that the white connector it is always on 0V the one that supplies the second part even the red led power is going on.To read

author: JKKDev
author_rank: Regular Contributor
timestamp: March 21, 2020, 05:33:57 am
content: The community is more than willing to help you but you have to actually respond to their requests.As people above have mentioned please open the device and take a few pictures of the internals. This will help with diagnosing the issue.Your request for information based on nothing but a few measurements is an impossible task except for maybe the small group of people that might have owned/repaired this exact unit before.Based on this I'd suggest you answer ALL of this questions:- Are you willing to open the unit up? If so take pictures of the insides.- What kind of test equipment do you own / you can use to diagnose the fault?- Do you have any prior experience with working on this type of equipment? (I'll be honest, I've got no idea if this is battery or mains powered)And finally a line of thinking that so many people seem to miss these days: It's already broken Bob, it's of no use to you so why don't you at least try to fix it. You can always throw it in the bin later.

author: Neilm
author_rank: Super Contributor
timestamp: March 21, 2020, 05:30:50 pm
content: Quote from: HUGOMAN on February 27, 2020, 10:59:02 pmThe MIT515 is only rated for 600 Vac. If you have been able to apply 1999 Vac to it I am very surprised. Did you measure how much current was passed from the supply when you did this? Like most insualtion testers, the MIT515 will discharge a load at the end of the test. In this case by the expedient of putting a reasonably low value resistor accross the terminals. Putting 2 kVac into is sounds like the resistors are damaged which may mean the output filter stage is damaged.As you can chage the battery in it, just opening the case by undoing the 4 screws on the bottom should not invalidate any warrenty on it, just don't open the HV enclousure.

author: starnettelco
author_rank: Newbie
timestamp: October 15, 2025, 03:15:50 am
content: This is my problem too. we Have a PWM 2845B SMD 8 pins on step up tension pcb. pin 2 no have trigger to enable the PWM. we Have others OP AMP 3140 and LM311 to control this signal but without schematics is no so simple trailing. Iwill trace the schematic for signal main lines of step up tension circuit pcb. Service manual is no possible found. Make a schematic Is only option. Good time when schematics went with equipaments.