Design of current flow control system
Design of current flow control system
(OP)
I have a "system" which I install into vehicles which I need to have the ability to fine control the current flowing into the system. My original thinking was to use a variable resistor inline of the positive but I dont think these will be up too the job.
Essentially the "system" will be set to allow a max of 10A flow at 13.8V, the resistance being set by the "system". I need to be able to adjust between 0A and 10A in this scenario.
My installations so far have been to take power direct from the battery (both + & -) and take them into a Ring Smart Relay RCT460 to detect when the engine is running and provide power down to the system. I have then had to adjust the current drawn by changing the "system" internally to get the required amps. This is a very fiddly job and takes time which can be better spent hence my request here.
So my request here is simple....does anyone have the ability to draw me a diagram of how to build a unit that will do 2 functions outlined underneath.
1. Replace the need for a seperate smart relay without the need to find an ignition live
2. Allow fine control of the current taken by the "system" (I call this choking it back) whilst leaving the voltage the same.
Here is hoping you can help me in my quest.
Kev
Essentially the "system" will be set to allow a max of 10A flow at 13.8V, the resistance being set by the "system". I need to be able to adjust between 0A and 10A in this scenario.
My installations so far have been to take power direct from the battery (both + & -) and take them into a Ring Smart Relay RCT460 to detect when the engine is running and provide power down to the system. I have then had to adjust the current drawn by changing the "system" internally to get the required amps. This is a very fiddly job and takes time which can be better spent hence my request here.
So my request here is simple....does anyone have the ability to draw me a diagram of how to build a unit that will do 2 functions outlined underneath.
1. Replace the need for a seperate smart relay without the need to find an ignition live
2. Allow fine control of the current taken by the "system" (I call this choking it back) whilst leaving the voltage the same.
Here is hoping you can help me in my quest.
Kev





RE: Design of current flow control system
Bill
--------------------
"Why not the best?"
Jimmy Carter
RE: Design of current flow control system
RE: Design of current flow control system
However, on a more fundamental note, what you are asking for will not physically work, based on the limited information you have provided. You cannot arbitrarily reduce the operating current of a piece of electronics. The "resistance" as you describe is integral to the proper operation of any circuit. That applies equally to motors, actuators, lights, radios, etc.
TTFN
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RE: Design of current flow control system
So what I need is a programmable current PS...that helps me narrow down the search on google.
As an aside given that I want to merely reduced the current flow by increasing the resistance and the voltage is constant (or virtually) at 13.8V (alternator output) this has got to be possible. It is not driving a motor or anything similar....the "system" I speak of is able to handle any amount of current from 0.2A up to 10A (resistance range of 69 - 1.38ohm) based on the limit set be the system. All I want to do is throttle back the current to be able to tune it to the vehicle and thought that this would be a simple solution. It appears I am mistaken unless others have other solutions.
RE: Design of current flow control system
TTFN
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RE: Design of current flow control system
Ignore the "system" from now on and replace it with resistor at 1.38ohms.
The new unit will need to replace the Ring Smartcom Relay (part No RCT460) which is a device that detects when the alternator is operating and supplies power to the 1.38ohm resistor.
The new unit will also need to be able to control the current being supplied to the 1.38ohm resistor. Current is the key here but how it is done I dont mind.
Sorry for the basic diagram but I aint no electrical guru.
If you need any further information let me know.
RE: Design of current flow control system
I really suggest that you get at least a college student who has taken at least one year's worth of electronics and gotten good grades...
TTFN
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RE: Design of current flow control system
The "system" will not change its own resistance....I can change it at time of install but wish to have a set resistance and then use the new electronic item to change the current drawn.
RE: Design of current flow control system
I'll reiterate... find a competent EE.
Dan - Owner

http://www.Hi-TecDesigns.com
RE: Design of current flow control system
Unfortunately, you thought wrong, unless you've actually got a transistor.
Again, if you have something that's like a resistor, then changing the current requires changing the voltage, but in a rather huge way, and you'd need a programmable voltage power supply. Again, you should get at least a smart BSEE student or a graduated EE to help you.
TTFN
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RE: Design of current flow control system
Live in North Wales
RE: Design of current flow control system
But 0.2 Amps at 13.8 Volts will be 69 Ohms. 69 Ohms minus 1.38 Ohms is 67.62 Ohms. Put a heavy wire wound resistor greater than 67.62 Ohms in series with your system and adjust it manually.
Bill
--------------------
"Why not the best?"
Jimmy Carter
RE: Design of current flow control system
h
The Help for this program was created in Windows Help format, which depends on a feature that isn't included in this version of Windows.