Graham Howard
New Member
- Messages
- 5
- Location
- UK/India
Aha ok thanks for that.....
- Thread starter Landslide
- Start date
CrazyTheCrip
New Member
- Messages
- 7
- Location
- Lithuania Vilnius
Emergency, paging dr. Jim, emergency 
"Link wires J and M in the pedal, not at the plug. I take a link from the leg of the pot J wire and go to the side of the micro-switch that joins the M wire.
J Goes to 10 K pot
C is pot wiper
F Goes to 10 K pot
R and M are connected to the switch
A goes to ground via a high voltage 1000v plus 2.8nF capacitor.
If you've got it right, with multimeter set to ohms and your probes on pins C - F, set the pedal in the up position and your meter will show around 10 K, then with the pedal depressed read Low ohms. Don't worry about the 10 ohms minimum bit, the resistance in the cable and the pot contacts will nearly give that on their own.
EDIT: Had a closer look at my drawing and the link is the key part, do it in the pedal, not the plug."
So in the Foot pedal, does pin A for the capacitor just connect to the body of the pedal ? My pedal only has 5 wires for pins M R F C & J.
J Goes to 10 K pot
C is pot wiper
F Goes to 10 K pot
R and M are connected to the switch
A goes to ground via a high voltage 1000v plus 2.8nF capacitor.
If you've got it right, with multimeter set to ohms and your probes on pins C - F, set the pedal in the up position and your meter will show around 10 K, then with the pedal depressed read Low ohms. Don't worry about the 10 ohms minimum bit, the resistance in the cable and the pot contacts will nearly give that on their own.
EDIT: Had a closer look at my drawing and the link is the key part, do it in the pedal, not the plug."
So in the Foot pedal, does pin A for the capacitor just connect to the body of the pedal ? My pedal only has 5 wires for pins M R F C & J.
A ceramic disc capacitor on a signal with the other end connected to ground is there to filter noise and high-voltage spikes to ground, and protect the signal circuit.
There are two parts to the voltage specification of the capacitor
- the working voltage - e.g. on a 230v mains circuit, a rating of 400v or more would be fine
- the highest value of a brief spike that it can safely withstand
The latter is described as the "X" or "Y" rating of the capacitor. A type "X" capacitor is typically placed across the AC power lines to filter noise, and a type "Y" is connected from Live - or signal - to Earth ( as in this case ).
A capacitor that is rated at "X1" can withstand an impulse ( spike ) of 4,000 volts ( typically used in industrial applications ) and an "X2" can safely handle 2,500 volts ( typically for domestic use ).
Where the capacitor is feeding to ground, a rating of "Y1" means 8,000 volts, and "Y2" is 5,000 volts.
I think you need a 2.8nF ( 2800 pF ) capacitor, rated at 400v working, and with a "spike-to-ground" rating of Y2, or better. Such as this one:
https://www.ebay.co.uk/itm/2-8nF-50...-AC-Line-Rated-Ceramic-QYT-1-PCS/182256257957
It is a Y1, which means 8,000 volts.
There are two parts to the voltage specification of the capacitor
- the working voltage - e.g. on a 230v mains circuit, a rating of 400v or more would be fine
- the highest value of a brief spike that it can safely withstand
The latter is described as the "X" or "Y" rating of the capacitor. A type "X" capacitor is typically placed across the AC power lines to filter noise, and a type "Y" is connected from Live - or signal - to Earth ( as in this case ).
A capacitor that is rated at "X1" can withstand an impulse ( spike ) of 4,000 volts ( typically used in industrial applications ) and an "X2" can safely handle 2,500 volts ( typically for domestic use ).
Where the capacitor is feeding to ground, a rating of "Y1" means 8,000 volts, and "Y2" is 5,000 volts.
I think you need a 2.8nF ( 2800 pF ) capacitor, rated at 400v working, and with a "spike-to-ground" rating of Y2, or better. Such as this one:
https://www.ebay.co.uk/itm/2-8nF-50...-AC-Line-Rated-Ceramic-QYT-1-PCS/182256257957
It is a Y1, which means 8,000 volts.
Last edited:
ive pm'd you too jim regarding supply of a foot pedal for a EWM Triton 220 ac/dc
