No, you have it wrong. Please allow me to do my best to explain. 
I smile to show I am not trying to be an ass.
The grey Dim- wire should not be connected to earth ground at any point. It is isolated for a reason, galvanically isolated. why? I don't know, but it is important.
Earlier I called it 0-10 volt dimming, Philips does as well, but it should really be called analog 1-10 volt dimming control. It gets confusing if we call it 0-10 volt dimming because the theatrical lighting folks have a different protocol, where there has to be an external current source for the control circuit.
In architectural lighting the ballast does, or atleast is supposed to source the current(and 10 volt potential). Philips explains it well here, though it is fluorescent product literature, the information (other than specific circuit mA ratings) holds true for the e-vision ballast. You can use an external isolated 0-10 volt DC power source, but you do not have to in order to take advantage of the dimming feature. It really only becomes necessary when you are trying to control the dimming status from multiple points in a room or other involved control logic.
So again, yes you can use a properly sized potentiometer to control the dimming status of the Philips e-vision ballast. You just use two of the three connections, the center and either outside contact. All we are really needing is a resistive load, to sink the current and drop the control voltage signal. The variable resistance of the potentiometer or rheostat gives us variable control. If you want step dimming you can use a rotary switch(or automate with PLC) and fixed resistors that sink the appropriate current to drop the control voltage to the desired value for each dimming step.
The common dimmers they sell at lowers for incandescent are no longer rheostats, they are triac phase choppers, and thus will not work to control the 1-10 volt dimmable ballast like the e-vision, dyna-vision, quicktronnic ect.
Luckily radio shack sells potentiometers in various sizes and shapes.
Somebody smarter than me should figure out the correct math and values based off the literature that I found saying each ballast sources 0.5 mA current on the control circuit. Because I am almost certain I mis applied ohms law in my previous post.
Travel safely,
I smile to show I am not trying to be an ass.The grey Dim- wire should not be connected to earth ground at any point. It is isolated for a reason, galvanically isolated. why? I don't know, but it is important.
Earlier I called it 0-10 volt dimming, Philips does as well, but it should really be called analog 1-10 volt dimming control. It gets confusing if we call it 0-10 volt dimming because the theatrical lighting folks have a different protocol, where there has to be an external current source for the control circuit.
In architectural lighting the ballast does, or atleast is supposed to source the current(and 10 volt potential). Philips explains it well here, though it is fluorescent product literature, the information (other than specific circuit mA ratings) holds true for the e-vision ballast. You can use an external isolated 0-10 volt DC power source, but you do not have to in order to take advantage of the dimming feature. It really only becomes necessary when you are trying to control the dimming status from multiple points in a room or other involved control logic.
So again, yes you can use a properly sized potentiometer to control the dimming status of the Philips e-vision ballast. You just use two of the three connections, the center and either outside contact. All we are really needing is a resistive load, to sink the current and drop the control voltage signal. The variable resistance of the potentiometer or rheostat gives us variable control. If you want step dimming you can use a rotary switch(or automate with PLC) and fixed resistors that sink the appropriate current to drop the control voltage to the desired value for each dimming step.
The common dimmers they sell at lowers for incandescent are no longer rheostats, they are triac phase choppers, and thus will not work to control the 1-10 volt dimmable ballast like the e-vision, dyna-vision, quicktronnic ect.
Luckily radio shack sells potentiometers in various sizes and shapes.
Somebody smarter than me should figure out the correct math and values based off the literature that I found saying each ballast sources 0.5 mA current on the control circuit. Because I am almost certain I mis applied ohms law in my previous post.
Travel safely,
