Hi All,
Bit of a newbie here when it comes to the 4-20mA sensor standard.
First, on the product page for the PR33-27 I see some documentation available for the onboard DAC and the loop transmitter (datasheets), and there are some pictorials under “drawings” but I really don’t see a user manual or datasheet for the actual transmitter board? What is the max voltage I can use in my current loop? What do the headers on the board do for “gain” and for “address” ? Maybe I am just missing where on the website this sort of thing is located.
Now, onto actually using this thing… what I’m trying to achieve is the following…
I have a portable hydraulic pump and controller that I would like to remotely monitor. Simple things like current sensing for the pump and tank levels. I have a I/O modem that runs off our local radio network that uses 4-20mA analog inputs. I would be working with our communications department to get the modem tracking data using Modbus. Conveniently, the pump, pump controller, and I/O modem all run off of 24V and the pump controller enclosure has a nice 24VDC supply inside… so naturally I will be stuffing all of these parts into the pump enclosure together.
I’ve had some experience programming Arduino modules in the past and I figured it would be easiest if I use some 0-5VDC sensors to do the current sensing and tank level readings, feed that into the Arduino Nano and use the PR33-27 to handle the 4-20mA output that my modem requires.
I see on the “drawings” tab that it shows two sensors with a power supply for each one in the loop of the sensor. It does not show any voltage limits for this loop. The data sheet for the XTR115 shows 7.5V-36V… should I just assume this is the case for the PR33-27 board? Also, if I am using two of the four outputs on the board, it shows separate power supplies for each channel… so I cannot just wire each of the loops to the 24V power supply that is powering my pump/controller/modem? I would need to purchase an individual supply for each channel? Would this be considered isolated supplies? Any guidance as to what I’m looking for to achieve this, or any documentation/examples online on how this looks when wired? Are there some common 12 or 24V supplies that have 2+ isolated outputs if this is what I need?
Additionally, for my sensor input to the Arduino Nano, the adapter pretty much blocks access to all of the inboard female headers that I could have potentially plugged into. I suppose I could rig something up and push some wires into place, strain relief them and then insert the adapter on top… or am I stuck trying to desolder the header pins on the arduino nano so I can put female headers on top so I can piggy back sensors onto it?
Sorry for the long post, hopefully someone can help out! Thanks!