All About Circuits Forum applying 480 volts to a 440 volt transformer
 Register Blogs FAQ Members List Today's Posts Search Today's Posts Mark Forums Read

 General Electronics Chat Discussion forum for general chat about anything electronics related, including asking questions about material in the All About Circuits E-book, Worksheets, and Videos.

#1
05-20-2009, 03:51 PM
 trognholt New Member Join Date: May 2009 Posts: 1
applying 480 volts to a 440 volt transformer

I am in the process of hooking a used injection molding press and this machine was rated as a 220/440 volt machine. Our in plant power that I will be applying to thiis machine is 480 volts. That 480 volts is going to be applied to a transformer that is rated for 220/440 that drops the voltage to 100 volts for the controller power. My main questions are concerning the transformer and if this will cause the transformer to burn out and if I will still get the same 100 volt output or will this increase to due the higher applied voltage?
#2
05-20-2009, 04:21 PM
 mik3 Senior Member Join Date: Feb 2008 Location: Cyprus, but now in UK (GMT+0) Posts: 4,846 Blog Entries: 9

The output voltage of the transformer will be 240V instead of 220V.

It will not be a problem because transformers are designed to be able to handle voltages around their rated values due to variations in the line voltage.

Is the voltage stable enough or does it varies a lot?
#3
05-20-2009, 04:58 PM
 thingmaker3 Super Moderator Join Date: May 2005 Location: Rural, Oregon GMT -8 Posts: 5,072 Blog Entries: 6

Quote:
 Originally Posted by trognholt Iand if I will still get the same 100 volt output or will this increase to due the higher applied voltage?
It will increase due to the higher voltage. At 480V in, the control voltage will be 109V. When the line surges to 500V (which is in keeping with specs for a 480V line) the control voltage will be at 113.6V. If your press controls can tolerate this, there is no issue. Maximum input voltage should be listed in the documentation for your press. If you don't have said documentation and cannot find it online, try contacting the press manufacturer.
__________________
"I want to establish in your mind very clearly that you must not think I deny all that I do not admit. On the contrary, I think there are many things which may be true, and which I shall receive as such hereafter, though I do not as yet receive them; but that is not because there is any proof to the contrary, but that the proof in the affirmative is not yet sufficient for me"
#4
05-20-2009, 05:11 PM
 Slider2732 Junior Member Join Date: May 2009 Location: Muskogee, OK, USA Posts: 17

Would be handy if there was an equivalent to logic circuits 7805 type voltage regulators.
78100 perhaps !
#5
05-20-2009, 07:44 PM
 mik3 Senior Member Join Date: Feb 2008 Location: Cyprus, but now in UK (GMT+0) Posts: 4,846 Blog Entries: 9

Quote:
 Originally Posted by Slider2732 Would be handy if there was an equivalent to logic circuits 7805 type voltage regulators. 78100 perhaps !
It is an AC voltage, it much complicated to regulate it with solid devices.

Power companies have taps on the transformers and change them according to the line load.
#6
05-21-2009, 12:51 AM
 steinar96 Senior Member Join Date: Apr 2009 Posts: 239

Isnt there a risk of core saturation if the voltage per turn is exceeded. Unless the core is made with alot more turns then needed for safety.
#7
05-21-2009, 01:19 AM
 mik3 Senior Member Join Date: Feb 2008 Location: Cyprus, but now in UK (GMT+0) Posts: 4,846 Blog Entries: 9

Quote:
 Originally Posted by steinar96 Isnt there a risk of core saturation if the voltage per turn is exceeded. Unless the core is made with alot more turns then needed for safety.
There is but I think transformers can tolerate voltages between 10% of their nominal value.
#8
05-22-2009, 05:54 AM
 THE_RB Senior Member Join Date: Feb 2008 Posts: 5,433

Transformers with light loads tend to overheat when the voltage is higher than spec due to the core losses. If your control circuit draws a relatively fixed current it is a typical industrial solution to put a series resistor to the power input to the transformer to drop the voltage 10% or so.

 Tags 440, 480, applying, transformer, volt, volts

 Related Site Pages Section Title Worksheet Negative feedback opamp circuits Worksheet Advanced electromagnetism and electromagnetic induction Worksheet Step-up, step-down, and isolation transformers

 Similar Threads Thread Thread Starter Forum Replies Last Post Talmadge General Electronics Chat 2 12-21-2008 02:56 AM fuadramsey The Projects Forum 11 08-05-2008 10:31 AM Erin G. Off-Topic 6 03-14-2008 09:58 AM Sean Reed Homework Help 16 03-01-2008 05:19 AM Bcog General Electronics Chat 3 01-22-2008 03:21 AM

 Thread Tools Display Modes Linear Mode

 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 Rules
 Forum Jump User Control Panel Private Messages Subscriptions Who's Online Search Forums Forums Home Electronics Forums     General Electronics Chat     The Projects Forum     Homework Help     Electronics Resources Software, Microcomputing, and Communications Forums     Programmer's Corner     Embedded Systems and Microcontrollers     Computing and Networks     Radio and Communications Circuits and Projects     The Completed Projects Collection Abstract Forums     Math     Physics     General Science All About Circuits Commmunity Forums     Off-Topic     The Flea Market     Feedback and Suggestions

All times are GMT. The time now is 11:04 AM.