[_] (OT) Basic electronics
Ben Butterfield
Ben.Butterfield at elanit.co.uk
Fri Aug 11 13:23:48 BST 2006
Watts = amps x volts
Amps = volts / resistance
The volts obviously stay the same and the current is dependant on the
resistance of the circuit. If the bulb is designed for 240V, then it should
have the correct resistance to limit the power output to 25W. Therefore, you
got a dodgy bulb, I reckons. ;-)
-----Original Message-----
From: underscore-bounces at under-score.org.uk
[mailto:underscore-bounces at under-score.org.uk] On Behalf Of Oliver Humpage
Sent: 11 August 2006 13:08
To: underscore at under-score.org.uk
Subject: [_] (OT) Basic electronics
A small question to aid me in my hobbying...
Did anyone do some basic electronics at school/uni?
I've got a 25W, 240V AC halogen bulb (G9 fitting, although that's not
important apart from the fact it's impossible to get a basic holder for it
that's not part of a fancy light) that I'm using as part of a model I'm
building, and the fact that it's 240V AC suggested to me I could just wire
it straight up to the mains. However, when I did so, it shone for about a
second before blowing.
It's been suggested that I need to put a resistor in series with it, to
limit the power flow to 25W? If that's right, how big a resistor do I need?
Or did I just get a duff bulb?
Thanks _ brain,
Oliver.
--
underscore_ list info/archive -> http://www.under-score.org.uk
______________________________________________________________________
This email has been scanned by the MessageLabs Email Security System.
For more information please visit http://www.messagelabs.com/email
______________________________________________________________________
- ---------------------------------------------------------------------
Elan is the world's leading IT&T recruitment company. For more information go to www.ElanIT.com.
- ---------------------------------------------------------------------
The contents of this email and any attachment are confidential to the addressee and are intended solely for the addressee's use. If you are not the addressee, you have received this email in error. If so, you must not disclose, copy or take any action in reliance on this email and any attachment. If you received this in error, please contact the sender and delete the material from your computer.
Although this email and any attachment have been checked for viruses, no liability is accepted by Elan in this regard. The recipient should carry out virus and other checks as it deems necessary to ensure that this email and any attachments will not adversely affect its systems or data.
Amps = volts / resistance
The volts obviously stay the same and the current is dependant on the
resistance of the circuit. If the bulb is designed for 240V, then it should
have the correct resistance to limit the power output to 25W. Therefore, you
got a dodgy bulb, I reckons. ;-)
-----Original Message-----
From: underscore-bounces at under-score.org.uk
[mailto:underscore-bounces at under-score.org.uk] On Behalf Of Oliver Humpage
Sent: 11 August 2006 13:08
To: underscore at under-score.org.uk
Subject: [_] (OT) Basic electronics
A small question to aid me in my hobbying...
Did anyone do some basic electronics at school/uni?
I've got a 25W, 240V AC halogen bulb (G9 fitting, although that's not
important apart from the fact it's impossible to get a basic holder for it
that's not part of a fancy light) that I'm using as part of a model I'm
building, and the fact that it's 240V AC suggested to me I could just wire
it straight up to the mains. However, when I did so, it shone for about a
second before blowing.
It's been suggested that I need to put a resistor in series with it, to
limit the power flow to 25W? If that's right, how big a resistor do I need?
Or did I just get a duff bulb?
Thanks _ brain,
Oliver.
--
underscore_ list info/archive -> http://www.under-score.org.uk
______________________________________________________________________
This email has been scanned by the MessageLabs Email Security System.
For more information please visit http://www.messagelabs.com/email
______________________________________________________________________
- ---------------------------------------------------------------------
Elan is the world's leading IT&T recruitment company. For more information go to www.ElanIT.com.
- ---------------------------------------------------------------------
The contents of this email and any attachment are confidential to the addressee and are intended solely for the addressee's use. If you are not the addressee, you have received this email in error. If so, you must not disclose, copy or take any action in reliance on this email and any attachment. If you received this in error, please contact the sender and delete the material from your computer.
Although this email and any attachment have been checked for viruses, no liability is accepted by Elan in this regard. The recipient should carry out virus and other checks as it deems necessary to ensure that this email and any attachments will not adversely affect its systems or data.