We’ve always enabled the bus termination resistors in a particular instrument when communicating with them using an SDM-SIO1A. However when I do that with the present interface it isn’t able to communicate.
We have another RS485 interface which can communicate with the instrument with the bus termination resistor enabled.
Are you aware of there being any faults with these units that could cause this? Any other suggestions?
I’ve just found an older SDM-SIO1A which I’ll test tomorrow to see if it exhibits this issue or not.
Hi, I've found some spares of the SDM-SIO1A and the instrument and done some more testing and have concluded that the particular instrument was faulty, not any Campbell equipment.