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Old 05-03-2005, 03:23 PM   #1
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Default question about scoti diode

Which scoti diode should i choose 100v 3 amp or 400v 3amp???
the scoti diode that came with qc2 was 400v 0.75amp (540bl).
the higher amp the scoti diode is better or the voltage? thanks.
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Old 05-03-2005, 03:41 PM   #2
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A higher amp one is advisable.
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Old 05-03-2005, 10:12 PM   #3
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ok scoti diode getting the higher amp...how about the voltage???
will 100v be sufficient or 400 volt will be better...thanks.

another q. for power capacitor...which 1 is better 16v 6800uf or 25v 6800uf. sumone plz help.thanks...
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Old 05-03-2005, 10:49 PM   #4
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Quote:
Originally posted by EngTat
ok scoti diode getting the higher amp...how about the voltage???
will 100v be sufficient or 400 volt will be better...thanks.

another q. for power capacitor...which 1 is better 16v 6800uf or 25v 6800uf. sumone plz help.thanks...
Get the 16v cap, 25v is more than you need, it would just take longer to charge up.
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Old 05-04-2005, 01:18 AM   #5
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get the 16 V it will be smaller and take a cap with a low ir and who can work at hiqh frequencies.

The diode must be a Schottky diode
one of the best axial diode will be the ref 90SQ040 (9A diode)
You can use some diode in to220 size that you can (like the novak 35 A) leave that on the speedo.
of course it's better to place a diode near the motor.

Hope you anderstand me because i'm french !
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Old 05-04-2005, 02:04 AM   #6
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Schottky diodes: bigger amp is better than voltage. See my attachment for the ultimate schottky diodes.

Capacitor : bigger capacity ( uF ) is better up to certain limit. Too big size cause unnecessary weight and even less performance. 16V rating is good for RC application. Try to find low ESR type ( fast charge / discharge ) you could easily find them from older computer motherboards like Pentium 2 and 3.
Attached Files
File Type: pdf sbl3040.pdf (26.3 KB, 5745 views)
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Old 05-04-2005, 09:52 PM   #7
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thanks everyone...i saw the kopropo power capicitor was 25v 2700uf not sure about the uf does bigger uf help alot or any will do?thanks

and wouldnt the esc burn as it is rated to operate at 4.8~8.4v...while the diode 1s 25v.
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Old 05-04-2005, 09:57 PM   #8
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Quote:
Originally posted by asw7576
Schottky diodes: bigger amp is better than voltage. See my attachment for the ultimate schottky diodes.

Capacitor : bigger capacity ( uF ) is better up to certain limit. Too big size cause unnecessary weight and even less performance. 16V rating is good for RC application. Try to find low ESR type ( fast charge / discharge ) you could easily find them from older computer motherboards like Pentium 2 and 3.

i am a lil confused the diode is 3 led diode, how am i going to mount to the motor.thanks.
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Old 05-04-2005, 10:11 PM   #9
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uf is the measurement microfarad. Capacitors basically store electrical current and in the case of an RC application release it quickly when a path to ground (ie neg batt) is made availible by nailing the throttle. It improves punch in stock 19t by allowing a rapid release of amperage to the motor, but is also useful in all forms of rc because it helps to reduce emf related intereference caused by the high current components of an rc car. The schoktty diode (like all diodes) only allows current to flow in 1 direction. When you apply the brakes current flows back into the speedo from the motor and can damage the breaking fets if it is too high, or in the case of some speedos virtually any reverse current is damaging (the KO's come to mind). The link posted previously is awesome and really overkill (in a good way!). + I am sure buying it from an electrical supply distributor like newark or mouser will cost a lot less than comprable KO ultimate schokkty which costs $40!
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Old 05-04-2005, 10:18 PM   #10
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Quote:
Originally posted by eforer
uf is the measurement microfarad. Capacitors basically store electrical current and in the case of an RC application release it quickly when a path to ground (ie neg batt) is made availible by nailing the throttle. It improves punch in stock 19t by allowing a rapid release of amperage to the motor, but is also useful in all forms of rc because it helps to reduce emf related intereference caused by the high current components of an rc car. The schoktty diode (like all diodes) only allows current to flow in 1 direction. When you apply the brakes current flows back into the speedo from the motor and can damage the breaking fets if it is too high, or in the case of some speedos virtually any reverse current is damaging (the KO's come to mind). The link posted previously is awesome and really overkill (in a good way!). + I am sure buying it from an electrical supply distributor like newark or mouser will cost a lot less than comprable KO ultimate schokkty which costs $40!
about the power capicitor higher uf will do better job then the lower uf???
does we use smaller uf for stock and 19t since it draw smaller amp and bigger for mods???
thanks
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Old 05-04-2005, 10:25 PM   #11
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Default model number

Engtat: Can i have the model number of the schottky diode your using? Its printed on the diode itself. Thanks.
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Old 05-04-2005, 10:31 PM   #12
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Engtat: Can i have the model number of the schottky diode your using? Its printed on the diode itself. Thanks.
time being i am just using in5401 and sb540bl(ori from qc2)
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Old 05-04-2005, 10:35 PM   #13
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4700 uf (make sure it can handle the voltage) is around the right area. Although I've seen people use up to 10000uf caps.
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Old 05-04-2005, 10:41 PM   #14
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Quote:
Originally posted by eforer
4700 uf (make sure it can handle the voltage) is around the right area. Although I've seen people use up to 10000uf caps.
voltage...is the 16v 6800uf ok? of higher v is better?ko propo 1s is 25v if not mistaken.
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Old 05-04-2005, 10:43 PM   #15
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Default Re: model number

Quote:
Originally posted by diesel
Engtat: Can i have the model number of the schottky diode your using? Its printed on the diode itself. Thanks.
diesel do u now how much is the ko scoti diode the old model when like printed board, i can t remember the part number. my lhs is selling rm28 i think.
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