Normalizing 1 Meg ohm DVM meter plug

[DexterMccoy]

Normalizing 1 Meg ohm DVM meter plug
At work we use these 1 Meg ohm Normalizing Black box with banana plugs that goes to the DVM meters inputs RED and BLACK probes

What are these Normalizing boxes do for DVM meters? it puts a 1 meg ohm resistor across the DVM meter probes for measuring voltage

It's to make a normalizing circuit , which is a voltage divider it looks like

But when do you use these normalizing circuits to do voltage measurements?

a resistor decade box in series to get a 10volts dc reference

We use the 1 meg ohm Normalizing plug which goes across in parallel in the DVM meter input jacks, then we use a resistor decade box in series , we rotate the resistors decade box until the DVM meter reads 10 volts DC. This is called a Normalizing circuit

I'm not sure what this normalizing circuit is or why it is used to take certain measurements

I don't understand the theory or why would want to "normalize the meter readings?

What circuits or tests would you want to normalize the meter readings?


Do you now understand the concept of "normalizing?"
No I don't, please explain to me what it is and what it is used for please?

When have you used to "normalize" the DVM meter readings?

What circuits or tests would you want to normalize the DVM meter readings?

Without normalizing the DVM meter readings what would happen? the readings would be to hard to make sense?

 

[ronsimpson]

It is hard to know what is happening but I will give it a go.

I think you are right about the voltage divider idea. Also this thing probably has a long history. I think many years ago they used meters with 1meg ohm inputs. Now those meters are gone and you can only get meters with 10meg inputs. Now the voltage divider will not work right so they place a 1meg resistor (maybe 1.1meg) across the meter to make it act like the old meters.

My guess on the "normal" subject: You have 12 volts and they want a measurement that tells you what percent error there is. So 10% high 12 volts is 13.2 volts but that is hard on the head. So they make a voltage divider that makes 12.0 read 10.0. Now 10% high reads 11.0 units. (not volts but units)

I have seen this type of metering used on radio transmitters. I had a 20,000 watt transmitter. Every hour someone that lacked training had to write down the power readings in percent. So the meter read 100% at 20000 watts. In the log book the numbers read 100, 101, 99, 98. There was a red line at 105 and 90 the two limits. So the meter was "normalized" to 100.

We often did this in the factory. Some days we made 12V power supplies and other days 15V supplies. The test machine read 100 then the voltage was right for that test.

 

[DexterMccoy]

So the meter was "normalized" to 100.

So what other ways is there to normalize meter readings? is it always using these voltage dividers?

The Decade box i think is used to match the impedance of the circuit?

But since the decade box is on the negative side or bottom side of the voltage divider it acts like a normalizing instead of matching the circuits impedance with the DVM meters impedance

Because the decade box would have to be on the upper side or top side of the voltage divider to be matching the impedance , but the decade box is on the bottom side of the 1 meg ohm resistance, doesn't this change the voltage divider effect?

The 1 meg across the DVM meter changes the DVM meter input impedance?