Multimeter + measurement in a 3-phase installation (question)?

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• #1
lukaszzk
Level 14
Hello

I have a question about "measuring" a 3 phase installation.
One day I decided to play with my multimeter (so far I have not made any measurements of the 3f installation, so maybe I do not know about something).
So I have 3 questions:

1. in my opinion, the voltage between each phase and the neutral point should be 230V, and the voltage between phases, i.e. between 2 phases, should be 380V, am I right?

2. Can you perform measurements in a 3-phase installation with a multimeter with the option of measuring AC voltage up to 750V?

3.Today I just burned my first good meter, it broke when I wanted to measure the inter-phase voltage between 2 phases, first I measured the voltage in the socket and everything was fine, the reading is almost 230V, then I wanted to measure the voltage between 2 phases and here to my surprise I saw a black balloon from the meter and a flash in the fuse, currently I am looking for an answer to the cause of this event, I do not know why the meter damaged just when measuring the phase-to-phase voltage
(for those interested, the cables were well inserted into the respective sockets of the meter, and the measuring range was also set to ~ 750V.

3.a can someone explain this event to me?
3.b Can you measure the voltage with a neutral conductor and any phase with a multimeter?
3.c are there any other devices for measuring the inter-phase voltage (once when my hydrophore motor damaged, the electrician had a fairly large meter), if so, I would be grateful for the name and if it was possible to provide a link to I was looking for an online store where you can get something like this, but unfortunately I found nothing.

• #2
Anonymous
Anonymous
• #3
lukaszzk
Level 14
Thanks for your answer, but I still have my doubts and as for your electrician, it was definitely not a bulky multimeter.
Still don't know what to measure phase-to-phase voltage?
#4
Topolski Mirosław
Moderator of Electrical engineering
lukaszzk wrote:

Still don't know what to measure the inter-phase voltage?

Maybe you will provide the data of your meter first? everything is possible there).
#5
twardyboro
Level 16
Hello.

The interfacial tension can be measured as much as possible - you can see my friend had some kind of bad meter. I used to have a UNI-T M890G multimeter - it could withstand the phase-to-phase voltage even if it was turned on for resistance or continuity measurements. My colleague had a multimeter from another company with similar capabilities (bought on the stock exchange for PLN 40) and as I accidentally connected it to 230V in the 200? range, it is black soot, gray smoke - flash bang and after the meter.

Regards.
• #6
lukaszzk
Level 14
I have (or actually had) a German company, exactly the same as below:
http://www.allegro.pl/item219687228_niemiecki_miernik_uniwersalny_furstmann_255_temp_.html
I would like to add that after the damage, I decided to unscrew it, inside it was completely melted several paths, even on the housing from the inside there was a sign as if it had arisen as a result of overvoltage, in addition, at the end of the measuring cable there was a slight melting (on the pin), also the socket in the meter became a little bit taking a smoke.
(the meter was set to 100% good, the cables were also well connected)

Can you measure phase-to-phase voltage with this FÜRSTMANN FM-255 multimeter?
(between two different phases)?
#7
Aleksander_01
Level 42
[quote = "

Can you measure phase-to-phase voltage with this FÜRSTMANN FM-255 multimeter?
(between two different phases)?
[/ quote]

Hello.
Of course you can, only you hit the bum.
Regards
• #8
lukaszzk
Level 14
So it's all clear
• #9
bonanza
Power inverters specialist
A colleague of mine recently had a similar unpleasantness in measuring between phases. During the filming, the silver from the paths of the range switch spreads over the springs. At low voltages you have inaccurate indications at most, suddenly 400V and BOOM! When the meter starts to freak out or prophylactically when replacing the battery, you need to unscrew the switch and wipe its area with an alcohol rag and coat it with transparent silicone oil (insulation and better slip). It hasn't disappointed me so far.
• #10
tprzemko
Level 22
Hello
A long time ago I read somewhere that two men measured the voltage on the transformer busbars with a multimeter before the main switch. The consequences of a short circuit in the meter resulted in the death of both men. From this article, I do not approach the power rails with anything.
Regards
#11
Kaz K
Level 20
in the installation at home, you can measure the voltage with whatever you want, as long as the meter has the appropriate range, while in workplaces it is measured with certified meters (they do not cost PLN 20-40 !!!!!). And with your meter, you were unlucky.
#12
atlantel
Automation specialist
Hello!
I fully agree with the tpzemko, for these reasons you should use "real" measures and not Chinese food for PLN 20 without any markings or with a counterfeit certification mark. For the measurement of such voltages, meters in the measurement category CAT IV 1000 V should be used, and at least in the measurement category CAT III 600 V, this also applies to the test leads. And it should not be counted that a meter below PLN 100.00 has such a category, and if there is such an inscription, it is false.
Regards
#13
marcino2000
Level 24
buddy don't be offended but your gauge is only suitable for ... ... weather forecasting. Good meters are, for example, the Metexes cost a few hundred dollars, but they are reliable, I use such a meter to take from several to several hundred measurements a day and all I do with it is to replace the batteries and from time to time cables. besides, they are almost armored.
#14
Aleksander_01
Level 42
marcino2000 wrote:
buddy don't be offended but your gauge is only suitable for ... ... weather forecasting. Good meters are, for example, the Metexes cost a few hundred dollars, but they are reliable, I use such a meter to take from several to several hundred measurements a day and all I do with it is to replace the batteries and from time to time cables. besides, they are almost armored.
6

Hello.
Exactly. I have also had metex for ..... 18 years. I damaged (at my own request) only the capacitance measurement. And what passed - I touched the measuring tip several times to the HV on TV or to the focus (6-7 kV).
Recently it withstood a short circuit (in the 20 A range) in a car, only the fuse blown.
You will get a good measurement accuracy with a meter for PLN 30, but well-protected meters cost much more.
• #15
bonanza
Power inverters specialist
The one about which I wrote that my friend broke, it was just 18-year-old yellow metex 3610. Error in handling excluded. I also have one.
• #16
lukaszzk
Level 14
Thank you for all the posts, now I'm smarter, I know what to consider when buying a multimeter

Regards lukaszzk