Please help me identify and wire this meter display

[zaph1]

A few years ago, I made an ATX power supply tester that displayed the voltage on each of the five lines in a computer power supply. It's been at least 6 years and I can't remember the manufacturer or how to wire this display for 200v.

According to the original plans, I have a 10k and 1ohm resistor coming off of the signal to be tested. And a ground.

Please help.

 

[srizbf]

from 200v input make a potential divider circuit(R1 and R2)

take the voltage across R2 and give it to INHI and INLO.

if the display is 200mv type then voltage across R2 should be 200mv for 200V.
if it is 2v type then across R2 have 2v for 200v input.

connect the battery in V terminals.

DP1, Dp2 are for decimal points .

hope it helps you certain extent.

srizbf
10thjune2010

Added after 22 minutes:

if it is 7106/7107 based displays then you can use the following values.


for the 200v (with 200mv fullscale type):
R1=10Meg and R2=10k
dp2 should be used for decimal point.

srizbf
10thjune2010

 

[zaph1]

Thank you, I just remembered the manufacturer. Lascar Electronics. I googled them and the logo matches!

10m and 10k resistors, got it. Sounds right, so I will get some and test it tomorrow. Thank you.

 

[zaph1]

Nope, not working right. I think the problem is the input selection. From my old project plans, I have determined that INLO would connect to the positive signal to be measured passing through to 10k resistor
AND ground. I don't have a ground in this unit, so can I connect it to the negative signal?

Added after 11 minutes:

Connecting to the negative signal didn't work, either. At 1vdc the meter displays 82, anything higher displays 1(meaning it can't measure the signal).

 

[srizbf]

i assume that it is a 7106 compatible lcd meter.

the normal connections are as follows:

9v battery between V+ and V-

inputs between INHI and INLO.

for 7106 devices INLO , COM and REFLO are connected together.

you can check on the ic pins.



if so then inputs between INLO and INHI will be as already said.

if you have the manual or short description of the unit then it
will be easier .

please check the above.

srizbf
12thjune2010