analog input card

[David Nelson 3]

i need an analog input card that can handle up to 15 volts dc. does ab make one? if so does any one have a part number? thanks david

[Ken Moore 23]

Not to my knowledge, but you could use a signal isolator/converter, such as this one: http://www.mooreindustries.com/cgi-bin/dow...&form=quick_reg Handles 0-30V, not cheap though, I think they are around $300.00 each.

[Smoke 0]

I was going to say that we use several LVDT's that are 15 vdc and we don't use a isolator/converter, but now that I think of it they are 15 vdc in and +/- 10 vdc out.

[David Nelson 3]

well i spoke too soon. if i had got into my electronics books first i would have found the exact thing i was looking for. using a zener diode (6.2v) and a 1k ohm resitor and a pre-punched circuit board . i made my self a linear volatge shifter for less than $10 amercian. it drops the voltage to roughly 5.5 volts less than the input. which at 15vdc i get roughly 10vdc and at 10vdc i get roughly 5 vdc ,its cheap and works excellent i hope some one else may be able to use it. thanks for the help guys

[TimWilborne 108]

15VDC = 10VDC 10VDC = 5VDC Am I correct in thinking 0-5VDC = 0 VDC? Probably fine for your application, just wondering for personal knowledge

[David Nelson 3]

yes tw you are correct the only bad thing is below 6 volts(which is the point the diode conducts) you do not have a reading. but for my app all i need is 9 to 15 volts, which with this device it is 4 to 10 volts which of course is within the range of an analog input card

[TimWilborne 108]

Ok thanks. Had never thought of that. I had an application a few years ago that could have used it and I went with a voltage converter. I will have to remember that next time. 5 points

[rswolff 9]

why not use an op-amp and scale it completely from 0-15 to 0-10? (should also be in your electronics book)

[David Nelson 3]

well i had these parts laying around, i would have had to order an op-amp. but that would be a good way to do it as well