The Green Industry's Resource Center

Prev Previous Post   Next Post Next
Old 09-06-2007, 03:03 AM
fixer67's Avatar
fixer67 fixer67 is offline
LawnSite Silver Member
Join Date: Apr 2004
Location: Tryon NC
Posts: 2,155
Originally Posted by Bill Kapaun View Post
Why would you need "TRUE RMS AC VOLTAGE"?
Seems to me, that anything resembling an AC Voltage is verboten!.
This can explain better than I can

Some meters will read a DC voltage even though the meter is set to AC. A meter that reads TRUE RMS AC VOLTAGE when set to AC will so no voltage when a DC voltage is applied. The meter looks for the voltage swing and AC voltage swings (cycles) and DC voltage does not. The words TRUE RMS will show up somewhere on the box or paper work for the meter. Use a GOOD name brand meter like Fluke and you will be OK. A lot of the cheap off brand meters are not TRUE RMS meters. And a cheap meter can not see a AC voltage riding on a DC voltage. Trust me on this one I have learned the hard way. When you are looking for a DC and AC voltage on the same line you need a meter that can tell the two apart. Lets say you have a 12 volt DC and a 20 volt AC on the same line. You set a cheap meter that is not TRUE RMS on AC it will read 20 volts AC but set it to DC and it will read 20 volts DC. OK lets say the voltages are switched and now you have 12 volts AC and 20 volts DC on the same line. The cheap meter will show 20 volts AC even though the AC voltage is only 12 volts and it is the DC that is 20. I have learn this the hard way.

Last edited by fixer67; 09-06-2007 at 03:13 AM.
Reply With Quote

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Layout Style:

Powered by vBulletin® Version 3.8.6
Copyright ©2000 - 2016, Jelsoft Enterprises Ltd.
Copyright ©1998 - 2012,™ - Grand View Media
All times are GMT -4. The time now is 10:29 AM.

Page generated in 0.13451 seconds with 9 queries