(800) 853-2651
SHOP NOW

Simpson 150 Amp Clamp

O

OliLt

Member
I obtained a Simpson 150 Amp Clamp as part of an estate. The included instructions indicate that this tool was originally intended to be used with an analog AC instrument with a sensitivity of 5000 ohms per volt containing either a 2.5, 3, or 5 volt scale. There is a multiplication factor that is then used to calculate the total amps depending on the volt scale used.

Can this tool be used with a digital multimeter? The scales on my meter are much broader that 2.5, 3, 5 volts AC.
 
I am getting lost in the discourse. Suppose I set my DVOM to the 2 volt scale. What do I need to do to?
 
You will have to do some interpolation. Your digital meter should have a high input impedance and be a negligible load. You could use 2.5 as full scale but you would need a 12500 ohm resistor which is not common. 15000 is very common and you would use 3 volts as full scale. The scale on your digital meter should make no difference as long as it is above 3 that is 10 or 20 vac.
For instance on the 300 amp scale the meter would read 3 volts or 200 amps will read 2 volts.

On the red 12 amp scale the multiplier is 4 and 3 volts = 12 amps of 2 volts =8 amps and so on
If I was doing it, I would use a 20K potentiometer and place across the meter leads and calibrate the reading to match the reading of a known good meter.
 
The simplest thing would be to find an old Simpson 260 meter and use it. Or a better idea may be to go on Ebay and buy one of the new digital AC/DC amp clamps for around $25.
 
Ok, I'm beginning to get it. Just one clarification: should the resistor, or potentiometer be in series or parallel with the meter leads. Thanks for your response.
 
The shunt is in parallel with the meter leads. You're lowering the input impedance of the multimeter so it looks like it's an analog voltmeter. If possible, get a precision (1%) resistor. Radio Shack resistors are typically 5%, which is enough to affect the accuracy of your readings.
 
Yes it should be in parallel. Or as suggested find a Simpson 260 or Triplett 630 or 310.
The Simpson has a 2.5 volt scale and Triplett has the 3 volt scale.
I still love my old Simpson 260 except when I need a precision measurement. I like to see that meter swing!
 
You must log in or register to reply here.

Similar threads

B
S7 200 amp Inverter Welder review $99
Replies
17
Views
3K
bc
B
Geo-TH,In
Leak tester for Centex Farmall
Replies
0
Views
522
Geo-TH,In
Geo-TH,In
Tractor Parts Tractor Manuals

We sell tractor parts! We have the parts you need to repair your tractor - the right parts. Our low prices and years of research make us your best choice when you need parts. Shop Online Today.

Copyright © 1997-2024 Yesterday's Tractor Co.

All Rights Reserved. Reproduction of any part of this website, including design and content, without written permission is strictly prohibited. Trade Marks and Trade Names contained and used in this Website are those of others, and are used in this Website in a descriptive sense to refer to the products of others. Use of this Web site constitutes acceptance of our User Agreement and Privacy Policy TRADEMARK DISCLAIMER: Tradenames and Trademarks referred to within Yesterday's Tractor Co. products and within the Yesterday's Tractor Co. websites are the property of their respective trademark holders. None of these trademark holders are affiliated with Yesterday's Tractor Co., our products, or our website nor are we sponsored by them. John Deere and its logos are the registered trademarks of the John Deere Corporation. Agco, Agco Allis, White, Massey Ferguson and their logos are the registered trademarks of AGCO Corporation. Case, Case-IH, Farmall, International Harvester, New Holland and their logos are registered trademarks of CNH Global N.V.

Yesterday's Tractors - Antique Tractor Headquarters
Website Accessibility Policy

Back
Top