ECN Electrical Forum - Discussion Forums for Electricians, Inspectors and Related Professionals
ECN Shout Chat
Top Posters(30 Days)
Potseal 11
Recent Posts
600 KW 120/208 3 Phase Y protection
by SteveFehr. 07/23/17 09:46 AM
1913 American Electrician's Handbook
by gfretwell. 07/20/17 01:08 PM
Green House wiring
by ghost307. 07/20/17 09:10 AM
Permit Snafus...AHJs and Contractors Jump in
by HotLine1. 07/18/17 08:06 PM
New in the Gallery:
SE cable question
Popular Topics(Views)
239,276 Are you busy
174,738 Re: Forum
167,113 Need opinion
Who's Online Now
0 registered members (), 69 guests, and 9 spiders.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate This Thread
#43967 - 10/26/04 06:28 AM Hey guys  
AndyP  Offline
Member
Joined: Aug 2004
Posts: 20
To find amperage would I use
I=E/R

The resistance of a circuit is 45 ohms. The input voltage is 10v. What is the resulting amperage?


Work Gear for Electricians and the Trades

#43968 - 10/26/04 06:41 AM Re: Hey guys  
pauluk  Offline
Member
Joined: Aug 2001
Posts: 7,520
Norfolk, England
Yes, the formula you quote is correct.

I = E / R, so 10 / 45 = 0.222 amps.

That's for a DC circuit or an AC circuit which is purely resistive. If an AC contains inductance or capacitance, then it gets a little more complex.


#43969 - 10/27/04 12:16 PM Re: Hey guys  
Lee  Offline
Junior Member
Joined: Sep 2004
Posts: 9
philadelphia,pa,usa
^^^
you mean 4.5


#43970 - 10/27/04 01:54 PM Re: Hey guys  
Radar  Offline
Member
Joined: Apr 2004
Posts: 349
Los Angeles, CA
I think 4.5 would be R/E (45/10), which isn't anything really.

10/45 comes out to .2222 on my calculator.


There are 10 types of people. Those who know binary, and those who don't.

#43971 - 10/27/04 01:58 PM Re: Hey guys  
ElectricAL  Offline
Member
Joined: Oct 2001
Posts: 597
Minneapolis, MN USA
45 ÷ 10 = 4.5

10 ÷ 45 = .222


Al Hildenbrand

#43972 - 10/30/04 11:45 AM Re: Hey guys  
AndyP  Offline
Member
Joined: Aug 2004
Posts: 20
.22 repteated

[This message has been edited by AndyP (edited 10-30-2004).]


#43973 - 10/30/04 05:33 PM Re: Hey guys  
Attic Rat  Offline
Member
Joined: Dec 2003
Posts: 524
Bergen Co.,N.J. USA
...Uh,..OK, so which is it?,.. 4.5,..or .222amps?? Now I'm confused... [Linked Image] [Linked Image]
Russ


.."if it ain't fixed,don't break it...call a Licensed Electrician"

#43974 - 11/01/04 05:46 AM Re: Hey guys  
Scott35  Offline

Broom Pusher and
Member
Joined: Oct 2000
Posts: 2,707
Anaheim, CA. USA
Russ;

Quote

...Uh,..OK, so which is it?,.. 4.5,..or .222amps?? Now I'm confused...


The total Amperes will be 0.222 A for this Circuit.

The Calculation I=E÷R would result in an Amperage of 0.222, if a 45 Ohm Resistance Load was connected to a Power Source with an output Voltage of 10 Volts.

Looks like this:

I=E÷R,
R = 45 Ohms
E = 10 Volts

E (10 Volts) / R (45 Ohms) = 0.222 Amps ("I")

Concequentially (sp?), the 45 Ohm load connected to a 10 Volt System, will draw 2.22 Watts of True Power from the Power Supply.

The "4.5 Amps" thing was incorrect for this scenario (E=10V / R=45 Ohms).
If the values were reversed, then the "4.5 Amps" thing would be correct, meaning if the system's Voltage was 45 Volts and the connected load's Resistance was 10 Ohms, the resultant Current Flow would be 4.5 Amperes - with a resulting True Power (Wattage) of 202.5 Watts drawn from the Power Supply.

Sorry that this was not pointed out clearly, and hope it has been cleared up with this reply.

Scott35


Scott " 35 " Thompson
Just Say NO To Green Eggs And Ham!

#43975 - 11/01/04 09:08 AM Re: Hey guys  
Attic Rat  Offline
Member
Joined: Dec 2003
Posts: 524
Bergen Co.,N.J. USA
...Thanx,Scott for clarifying that,...I was getting dizzy!!! [Linked Image] [Linked Image] [Linked Image]
Russ


.."if it ain't fixed,don't break it...call a Licensed Electrician"


Member Spotlight
Admin
Admin
NY, USA
Posts: 3,447
Joined: October 2000
Show All Member Profiles 
Featured:

2017 NEC and Related
2017 NEC
Now Available!

Shout Box
Powered by UBB.threads™ PHP Forum Software 7.6.0
Page Time: 0.017s Queries: 14 (0.002s) Memory: 0.8009 MB (Peak: 0.9668 MB) Zlib enabled. Server Time: 2017-07-24 12:49:17 UTC