Voltage instead of current for relative compression test
- WisdomWarlord
- Topic Author
- Offline
- New Member
Less
More
- Posts: 17
- Thank you received: 1
5 years 9 months ago #21712
by WisdomWarlord
Has anyone tried setting their scope for a min of something like 8vdc and a max of like 12, and then crank the engine over to see if you get a useful waveform for doi G a relative compression test? Is it a reasonable thing to do if you don't have a current probe? I don't have access to a car with compression problems, so I wouldn't get to see the behavior.
Please Log in or Create an account to join the conversation.
Less
More
- Posts: 4383
- Thank you received: 957
5 years 9 months ago #21717
by Noah
"Ground cannot be checked with a 10mm socket"
Replied by Noah on topic Voltage instead of current for relative compression test
Good question!
Voltage measurement is just fine for relative compression testing. Andy has gone over the set up in the past in the forum.
Remember that voltage and current are Inversley proportional, so the valleys of the voltage waveform will be representative of the peaks of an amperage waveform. Many scopes will have a setting to invert the waveform for you.
Voltage measurement is just fine for relative compression testing. Andy has gone over the set up in the past in the forum.
Remember that voltage and current are Inversley proportional, so the valleys of the voltage waveform will be representative of the peaks of an amperage waveform. Many scopes will have a setting to invert the waveform for you.
"Ground cannot be checked with a 10mm socket"
Please Log in or Create an account to join the conversation.
Less
More
- Posts: 4383
- Thank you received: 957
5 years 9 months ago #21718
by Noah
"Ground cannot be checked with a 10mm socket"
Replied by Noah on topic Voltage instead of current for relative compression test
Also, you could create a compression problem by removing a spark plug
"Ground cannot be checked with a 10mm socket"
Please Log in or Create an account to join the conversation.
Time to create page: 0.221 seconds