Multimeter & Oscilloscopes

Oscilloscope Clamps

The clamp ammeter These are used for measuring the current that flows through the cable under test. As it does not have direct contact with the installation, it causes very little interference to the signal. These work the same way as described previously in the “Multimeter Measurement” section except some oscilloscopes have the ability to convert the V reading into Amps.

Inductive clamp

This is usually used to display ignition signals by fitting it on the high voltage cable of cylinder number 1. Current that flows through it causes a current pulse due to induction in the winding in it. This voltage peak is used as a synchronisation trigger by the oscilloscope.