how to check 400v capacitor whith analog meter

If it has broken down and is now shorted or leaky, an ohmmeter will read a low resistance value and that indicates a bad capacitor. If it is an electrolytic type, hundreds of thousands of ohms would be normal and if it is a non-polarized type, infinity ohms would be normal. Give the capacitor time to charge up (the resistance will keep increasing with a good capacitor).

NOT TO 400V... make sure the cap is discharged before doing this measurement. Set your analog meter on resistance (ohms) and measure across the terminals. Note that an electrolytic cap will have a very low resistance if you measure it the wrong way, so make sure the red lead is on positive, and the black is on negative.

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capacitor

Alert: Dont measure such a cap unless you are 100% sure the cap is discharged. Otherwise, you run a high risk to damage your ohm-meter because it doesn't endure any input voltage.

If you are using an analog ohm-meter, you should see the indicator pin rise slowly until it stops at the top. That usualy means there is no leak in the cap.

PS...

Since your voltmeter has an internal resistance, that means there will always be current flowing in the circuit which won't be caused by the capacitor's leakage current.

Assuming a meter with an input resistance of 10 megohms, that meter current will be:

E METER VOLTS METER VOLTS I = --- = ------------ = ----------------- = 10µA/100V R METER R 10 000 000 ohms

So, if at any time during the charging process the current indicated by the milliammeter fails to decrease to