Changing Digital Volt Meter Range (YB5135D)? - Page 1
Forum section: electronics / projects

author: sequoia
author_rank: Unknown
timestamp: October 15, 2015, 07:55:36 am
content: I came across some cheap Chinese digital volt meter. It seems to be AC meter with 0-2V range. But looking the circuit board it seems like the range should be adjustable to 0-20V or 0-200V by just changing the "jumpers" (0 ohm resistors).Anyone come across these?I'd like to change this to 0-20V range which would be much more useful... I'm guessing that in addition to changing the voltage range jumpers, there might need to change some resistor (to 10x value) or add a resistor somewhere....

author: singapol
author_rank: Frequent Contributor
timestamp: October 15, 2015, 09:29:51 am
content: Hwere is the info that should help you find what you need to do:http://www.intersil.com/content/dam/intersil/documents/an02/an023.pdfhttp://8085projects.info/icl7107-based-digital-voltmeter-circuit-for-several-commonly-used-applications.htmlhttp://www.delabs-circuits.com/cirdir/analog/instrument/del30002.html

author: rdl
author_rank: Super Contributor
timestamp: October 15, 2015, 04:08:29 pm
content: It's usually easier to just buy what you actually need. Have you checked that the seller of that meter doesn't already offer other ranges?

author: Geronimo
author_rank: Contributor
timestamp: January 03, 2021, 05:44:47 pm
content: This post is old and maybe obsolete but I'm following a similar idea where I would like to lower the amps reading on an AC modell to get an additional decimal point.Swiching form AC to DC or changing the voltage range is not that difficult as I guess. The same device is sold as 20mV/200mV/2V/20V/200V/500V panel meter.The 500V model (as is mine) is showing 3M Impedance on the description, for the 20mV the impedance is told to be 10K, all other models have 1M ohms impedance.NOTICE: I have not tryed out yet to modify mine but will do as soon as I have more details/information.To my understanding and for changing the volts range or even from AC to DC and to what I have find out, one would have to move some zero ohms resitors.In the upper left is an arean withDCandACmarking and two zero Ohms resitors used as jumpers.The picture shown is showing the AC settings.Changing the "DC" jumper to the top and "AC" to the bottom should change between AC and DC reading.As far as I can tell you will need to populateU1andC20as well for the DC usage.C20is from what I have seen a canned10V 100SMD electrolytic capacitor. I can not tell of what value (nF or µF).Notice also the 2V AC model as show above is have a "W102" (1K) trimpot whilst mine (the 500V one) is having a "W502" (5K) installed asVR1.VR2 is not populated in any of the ones I have seen on pictures.Q3is also populated on some of the DC models of this meter. I can't tell howerver what part this is.For changing the voltage range:At the lower right edge of the board is a section with "200", "20", and "2" marking. This uses zero ohms resitors as jumpers too.Moving the "2" jumper down will probably change the shown meter to the 500V range.Puting the "20" or "200" jumper/resistor one up will set the meter to the according voltage value I guess.On the left side at the bottom edge is a section with "1", "A", "V", and "3" marking also populated with zero ohms resitors as jumpers.I could not yet figure out what those "jumpers" will cause or mean, I guess it is to set the display. Maybe to have Volts at the top and Amps at the bottom.In additionR4,R4A,R5andR5Acan be populated. My 500V AC panel meter has 3 MegOhms populated for R5A and 6.2 KOhms for R4.Thus I guess R4 to R5b has to do with the input inpedance. According to the pictures of the different models I have seen one could start with 1MOhm resitors to fiddel out.So far what I can tell about this device.Cheers,Geronimo

author: ANTTEC
author_rank: Newbie
timestamp: November 27, 2021, 01:59:15 pm
content: This is my meter with settings for DC Voltage 200 mV range.

author: johnwa
author_rank: Frequent Contributor
timestamp: August 24, 2022, 11:44:11 am
content: I know this is an old thread, posting for my own reference in the future, and hopefully to help others as well...If you want to add an "offset" adjustment to this meter, proceed as follows:Cut the track beneath the component "I1" (this was DNF on my unit)Fit a trimpot for VR2, say 10k.Fit R28, I used 47k on mine.Fit either of the components marked "2V5" or "V-" (next to R28) with a 0R jumper, according to whether you want a positive or negative offset. (Don't fit both though!)The range of VR1 (span adjustment) can be increased by reducing R2, probably best not to go below 1K.I did look at the possibility of adding a differential input, this was done by cutting the track beneath I1 (don't fit the offset adjustment option), and feeding the negative input into pin 38 of the chip. This does work, but the common mode voltage must be less than about 1.5V from the negative rail (pin 40), or erratic operation results. There is something in the datasheet about the integrator saturating, I did play around with this but didn't get to the bottom of it. So, this mod probably isn't that useful, though it might be enough to overcome a ground shift in some applications.

author: GEOelectronics
author_rank: Regular Contributor
timestamp: September 12, 2022, 04:23:39 am
content: Hello. Thanks for the update. Could you post or link to the YB5135D's data sheet? I need to disable the decimal point for my application.George Dowell

author: tunk
author_rank: Super Contributor
timestamp: September 12, 2022, 10:00:36 am
content: I guess he refers to the ICL7606 datasheet.https://www.renesas.com/us/en/document/dst/icl7106-icl7107-icl7107s-datasheet

author: johnwa
author_rank: Frequent Contributor
timestamp: September 12, 2022, 12:33:51 pm
content: Referring to the image that sequoia posted, there are three jumpers labelled 200, 20, and 2 at the bottom centre. If you move all of these to the 0/down position, it should disable all the decimal points.

author: GEOelectronics
author_rank: Regular Contributor
timestamp: September 12, 2022, 02:45:23 pm
content: Thanks for the tip about the 200/20/2 jumpers and how to set or remove the decimal point, tried it, and it works!George Dowellk0ff