Attenuator

[Pong]

Hi should I use attenuator when measuring piezzo injector with a currently probe, and is the new Pico TA197 10.1 attenuator compatible with older Picoscope that required TA010 20.1 attenuator?

[Steve Smith]

Hello and thank you for the post

When measuring current flow through a Piezo injector, no attenuation is required regardless of the PicoScope connected

The Guided Test will demonstrate how to apply the current clamp in this scenario https://www.picoauto.com/library/automo ... o-current/

Regarding attenuation, the TA197 10:1 attenuator has superseded the 20:1 TA010 model; could I ask which scope you are using?

Both the TA197 and TA010 are compatible with older scopes, however, we must be aware of the maximum input voltage of the scope.

For example, the 4423 scope has a max input of 100 V and therefore the 10:1 attenuator is fine for ignition primary circuits peaking at 500 V (500 / 10 = 50 V)

However, if you are using the 3423 or the 4823 the max input voltage is 50 V; and for ignition primary circuits peaking at 500 V you are on the cusp of exceeding the max input voltage of these scopes with a 10:1 attenuator. With that said, for the time the voltage peaks and 500 V and the minimal energy present you will be fine.

If you are using a 20 V max input scope, then additional attenuation would be required for primary ignition

Returning now to your measurements of Piezo injector voltage which can often exceed 200 V, you will be fine with the compatible TA197 10:1 attenuator for our older range of automotive scopes

I hope this helps, take care……Steve