Hi all
I am in the process of building a mains power monitoring box and although I had a nice digital "all-in-one" meter, I wanted to add some analogue metering just because I personally like how this looks.
Right or wrong, I purchased a 72mm x 72mm 220V rated class 1.5 45-55Hz frequency meter off of Ali Express (part URL available on request - photo attached for reference). This arrived today and being of the cautious type I thought I would connect it up to my variac to see how it behaved.
Lo and behold, the meter starts reading straight away with the variac set at its minimum, and the pointer moves up roughly linearly as I increase the AC voltage, reaching FSD at about 18V. A 50Hz reading is achieved at around 12V AC.
I have never used this type of meter before, but I note that whilst in the UK they are available from suppliers such as RS and Farnell, they start at £30 and go up from there - my meter cost US$7 from Ali Express. All the datasheets for the UK spec ones show that they can just be connected straight across the mains supply, but it's pretty clear if I do this with my meter then I'll fry it.
So my question is - is this meter a "fake" (e.g. an AC voltmeter which someone has stuck a 45-55Hz scale to), or is there a special way you should drive such meters that I'm completely missing.
Thanks in advance for your help
James
I am in the process of building a mains power monitoring box and although I had a nice digital "all-in-one" meter, I wanted to add some analogue metering just because I personally like how this looks.
Right or wrong, I purchased a 72mm x 72mm 220V rated class 1.5 45-55Hz frequency meter off of Ali Express (part URL available on request - photo attached for reference). This arrived today and being of the cautious type I thought I would connect it up to my variac to see how it behaved.
Lo and behold, the meter starts reading straight away with the variac set at its minimum, and the pointer moves up roughly linearly as I increase the AC voltage, reaching FSD at about 18V. A 50Hz reading is achieved at around 12V AC.
I have never used this type of meter before, but I note that whilst in the UK they are available from suppliers such as RS and Farnell, they start at £30 and go up from there - my meter cost US$7 from Ali Express. All the datasheets for the UK spec ones show that they can just be connected straight across the mains supply, but it's pretty clear if I do this with my meter then I'll fry it.
So my question is - is this meter a "fake" (e.g. an AC voltmeter which someone has stuck a 45-55Hz scale to), or is there a special way you should drive such meters that I'm completely missing.
Thanks in advance for your help
James