reading capacitor value from code printed on it?

Question

I have a circuit board with a capacitor that needs replacing (it got burned when an adjacent triac went out). The capacitor is a small "bead" shape, and has the code:

1C4 ME5

printed on it.

I can't find anything on the web about this particular code format - can anyone help me figure out what its value and max voltage is?

The circuit has another one of these capacitors, and I thought about pulling it and trying to test its value. My idea is to charge it up to a known voltage, and time how long it takes to discharge through a known resistor. My problem is that I don't know what the impedance of the DVM voltmeter is, and this will influence the discharge rate due to its parallel resistance. Any ideas on how to approach this? I guess I could do this experiment twice, using two different known resistor, and back out the meter resistance. Any better ideas? I don't have easy access to any good electronics bench equipment, so am looking for simple approach.

BTW, I could post a digital closeup photo of the capacitor if that would help.

Thanks.

Bill Christens-Barry

Peter Bennett · Accepted Answer

Any chance that it is actually 104 rather than 1C4 - if so, it may bean 0.1 uF capacitor - very common value for power supply bypasscapacitors.-- Peter Bennett, VE7CEI  peterbb4 (at)   new newsgroup users info :  and NMEA info:  Power Squadron:

Bill Christens-Barry · Answer

I have a circuit board with a capacitor that needs replacing (it got burned when an adjacent triac went out). The capacitor is a small "bead" shape, and has the code:

1C4 ME5

printed on it.

I can't find anything on the web about this particular code format - can anyone help me figure out what its value and max voltage is?

The circuit has another one of these capacitors, and I thought about pulling it and trying to test its value. My idea is to charge it up to a known voltage, and time how long it takes to discharge through a known resistor. My problem is that I don't know what the impedance of the DVM voltmeter is, and this will influence the discharge rate due to its parallel resistance. Any ideas on how to approach this? I guess I could do this experiment twice, using two different known resistor, and back out the meter resistance. Any better ideas? I don't have easy access to any good electronics bench equipment, so am looking for simple approach.

BTW, I could post a digital closeup photo of the capacitor if that would help.

Thanks.

Bill Christens-Barry

Geir Klemetsen · Answer

"Bill Christens-Barry"  skrev i meldingnews:Best sugestion: Go buy a capacitance meter.Second best suggestion: Build an oscillator that make use of _one_ capacitor. It's important thatyou are able to calculate the oscillation frequens for that particularoscillator. You have an formula f = (r, c). Turn this intoc = (f, r).Example:  page 8. The formula shouldbe like this:  T = 2 * R1 * C1 * ln( 1 + ( 2*R2/R3 ) )    ( T = 1/f )Turning the formula to calculate C:  C1 = T / ( 2 * R1 * ln( 1 + ( 2*R2/R3 ) ) )Hope this helps : )Geir

Bill Christens-Barry · Answer

In article , Peter Bennett  wrote:Yes, that turned out to be the answer! Careful inspection showed that some of the paint had chipped off.Thanks.-- Wm A Christens-Barry, PhDEquipoise Imaging, LLC

Geir Klemetsen · Answer

"Bill Christens-Barry"  skrev i meldingnews:Best sugestion: Go buy a capacitance meter.Second best suggestion: Build an oscillator that make use of _one_ capacitor. It's important thatyou are able to calculate the oscillation frequens for that particularoscillator. You have an formula f = (r, c). Turn this intoc = (f, r).Example:  page 8. The formula shouldbe like this:  T = 2 * R1 * C1 * ln( 1 + ( 2*R2/R3 ) )    ( T = 1/f )Turning the formula to calculate C:  C1 = T / ( 2 * R1 * ln( 1 + ( 2*R2/R3 ) ) )Hope this helps : )GeirBtw: This is second time i post this message. It doesn't show up in thenews-group after the first time I posted it.

reading capacitor value from code printed on it?

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