Re: Transmitting linear 4-20mA d.c. signal over fibre optic cable
- From: Gene S. Berkowitz <first.last@xxxxxxxxxxx>
- Date: Sat, 17 Nov 2007 23:35:52 GMT
In article <1195037301.672720.196260@xxxxxxxxxxxxxxxxxxxxxxxxxxxx>,
denbigh1974@xxxxxxxxxxxx says...
I posted this question on the sci.electronics.design forum and it was
suggested that I come here.
I have a signal conditioner which outputs a 4-20mA d.c. signal
linearly proportional to a measured input.
About 4 miles away is panel meter which displays the 4-20mA d.c.
signal. The amplifier is connected to the meter by a screened twisted
copper pair.
I have now been requested to decommission the copper wire and replace
it with a fibre optic cable.
The following product has been recommended to me.
http://www.addvid.co.za/html/ll120.htm
It's exactly what I need except that it can only transmit up to two
miles. Can anyone suggest an alternative, please?
(There is power available at both the transmitter end and the panel
meter end.)
I looked at the datasheet for that device, and it isn't clear what the
resolution of the converted signal is. The specs list "960
samples/sec", which implies an A/D converter, but the only accuracy spec
is "100 uA deviation"...
A bit of googling returned Weed Instruments, who offer analog to fiber
multiplexers capable of 40 km:
http://weedinstrument.com/product_groups/fiber/multi.html
--Gene
.
- References:
- Transmitting linear 4-20mA d.c. signal over fibre optic cable
- From: denbigh1974
- Transmitting linear 4-20mA d.c. signal over fibre optic cable
- Prev by Date: Re: Approximating Differential Equation on the Basis of Measured Values
- Next by Date: Re: Approximating Differential Equation on the Basis of Measured Values
- Previous by thread: Re: Transmitting linear 4-20mA d.c. signal over fibre optic cable
- Next by thread: Re: "Rhetoric for Engineers" available FREE!
- Index(es):
Relevant Pages
|
