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DC Dummy load analog I OUT voltage conversion (Itech IT8500+ series)

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lukasz.kostka:
Hi

I've bought a ITech IT8511A+ DC dummy load. It has a BNC I OUT connector which outputs 10V/30A. All works fine on that output, problem is that ratio 3:1 is a odd value. My scope Rigol DS1054Z doesn't have any probe setting to scale it to a reasonable value. I've tried math as well but no luck. I've added a resistor divider to output with 3:1 ratio and all seems to work. Adding 2k, 1k results in too big load and signal is distorted. 20k, 10k is better. I think I will go with 200k, 100k 0.1% precision resistors.

My question to you guys is this a valid good approach ? Seems simple to me. I did consider using a opamp but no way of powering it and requires a fast opamp with some external power supply.
What do you think ?

Vovk_Z:
Without reading a device Technical Manual I can guess that a >10k load and <100k has to be fine.
100k and more - will interact with your oscilloscope input resistance (1M), and the whole divider will be less accurate.
At the same time, we must take into consideration a frequency range. The wider - the smaller resistance a divider must have (otherwise it must be compensated).

lukasz.kostka:
Unfortunately Itech doesn't provide detailed specs. I've attached manual.
Ok so best would be to choose resistors >10k and < 100k ?

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