So the other day, I got a manometer, which I had thought would be fairly self-explanatory to hook up. However, with a limited working knowledge of electronics, and a complete lack of ability to get good documentation on these, it has presented a couple of problems.
It has 6 output pins: sig out, pwr common, -15vDC, +15vDC, sigcom, and chassis. As the pressure inside changes, it outputs a voltage between 0 and 10V.
so, If I read this correctly(possibly?), sig out is one lead of the voltmeter, sigcom is the other, chassis should be... electrically grounded to some big piece of metal?
I also may be wrong about the other 3, but as I read it, I should get a 30 volt power supply (should a simple transformer work, or would it be too noisy coming from standard 120vAC?) and make a voltage divider circuit, with one end hooked up to -15v, the middle hooked to pwrcom, and the other hooked up to +15v. Is any of that right? Also, is there somewhere I could find a good diagram for it? I'm not sure what I'm looking for, what kind of resistors to use, or even what kind of amperage this thing should pull (though I can't imagine it would be a lot).
I thank you most sincerely for any help, pardon the electrical noobishness
You need a +/-15v supply. While you can use a voltage divider, it is not efficient. Make separate power rails from your transformer. You could use each half of a 30v centre tap for each. The common from these supplies goes to the power common. The sig common may also be the same as the power common.
The output being 0-10v is too big for the Arduino so use a divider to reduce it by half.
Chassis gnd is probably not important in many cases. It just connects to the body of the sensor. It would only be necessary in mains voltage situations where the body is not earthed by the mounting method.
Ther are many circuits available for the power supply via Google.
This one from ebay is has more output than you may need but is the right type of supply. The fact that it's a "linear" makes it quieter than many switchers. You're getting your sensor off e-bay so ....
OK, now the "chassis" should not be connected to any other part of the electronics. You may connect it to the power (mains) ground of your power supply and to other grounds to ensure the casing cannot become live - though this should not be a risk in respect of your measuring equipment, more likely something else in the plumbing.
Power ground and signal ground should be connected inside the device, so you connect your power supply to the three power supply terminals and your Arduino ground to the "signal ground". This means you should not need any other connection between the power supply for this unit and your Arduino system.