Hee guys,
I need some help with a project i'm working on. I have a XTR110 with a voltage divider connected to the input. The input voltage is 0-40V, the voltage divider converts this in to 0-10V (33k // 11k resistors(metal-film 2W 1%)). I use the simple schematic out of the data sheet (IRF9510 MOSFET) and 24V voltage supply.
The voltage divider works perfectly and the XTR110 work perfectly(with an input from 0-10V) but when i connect those 2 together, the output current changes. With 0-10V input, the output is 4-20 mA. With the voltage divider in front of the circuit, the output become 4-16mA. (input voltage still 0-10V from the divider)
When 1 measure the voltage from the voltage divider at 40V input -> 10V. When i connect it to the XTR110, the voltage divider drops to 7.7V. Is this because the XTR110 uses current from its input somehow?
I changed 1 resistor, so now it is 33K // 20K and the output current is 4-21 mA. But it still makes no sense to me.
Can someone help me?
Robert