WIRING QUESTION

[Fasouli]

Hello
I am planning to do my 737 mip and ovh panel but i have two questions , firstly :
I have read the Opencockpits master card manual and i know that on every input group on the master card there are 9 pins + 1 gnd so my question is how am i going to connect 1 gnd wire for 9 other wires . should i connect them all together so that they will then share one gnd pin . And my other question is when wiring all the knobs , switches and annunciators is this wire suitable for connecting them to the master card Cable 0,5 (para cablear la cabina )
thanks

[fordgt40]

Yes to both questions. When planning your wiring to the switches, you need to allocate the rotary switches first so that you can make sure that all the needed pins are within one "group" of 9 inputs. Spare inputs within the group of 9 then be filled up from other switches. The common ground wire should be daisy chained between the switches that are within the group before terminating at the mastercard ground pin.

David

[Fasouli]

Yes to both questions. When planning your wiring to the switches, you need to allocate the rotary switches first so that you can make sure that all the needed pins are within one "group" of 9 inputs. Spare inputs within the group of 9 then be filled up from other switches. The common ground wire should be daisy chained between the switches that are within the group before terminating at the mastercard ground pin.

David

I have searched for the term daisy chain but it only gives me a example on usb or headphone cables can you give me an actual example because it seems that i still didnt get the concept
Thanks

[fordgt40]

Ok

Lets suppose that you have a 4 position rotary, 2 x 2 position toggle switches and a push button.

Then you would run the ground wire from the centre of the rotary switch (that is generally the common pin) to the centre pin of the first 2 position toggle switch. Then on to the centre pin of the next toggle switch and then on to the "push button" switch and then finally to the mastercard group ground terminal connector. That way each switch has a linked common wire which terminates at the mastercard. All the other used pins on these switches are wired independently to the master card inputs within the group served by the common ground

David

[Fasouli]

Ok

Lets suppose that you have a 4 position rotary, 2 x 2 position toggle switches and a push button.

Then you would run the ground wire from the centre of the rotary switch (that is generally the common pin) to the centre pin of the first 2 position toggle switch. Then on to the centre pin of the next toggle switch and then on to the "push button" switch and then finally to the mastercard group ground switch. That way each switch has a linked common wire which terminates at the mastercard. All the other used pins on the switches are wired independently to the master card inputs attached to the common group ground

David

You have saved me hours of researching THANK YOU

[fordgt40]

Glad to help. Also, please note that I have edited my earlier post to remove a typo and hopefully clarify the meaning

[Fasouli]

Glad to help. Also, please note that I have edited my earlier post to remove a typo and hopefully clarify the meaning

Well i have another question . On my first post i inserted a link for cockpit wiring from OC. If i order it must i tell them that i need for example a red wire or it doesnt matter which color i use also if i order the wires can i use ANY wire as my gnd wire or must it be a specific kind
THANKS

[fordgt40]

The electronics do not know or indeed care what colour wire you use

Logic suggests you use a colour such as black for grounds, and use the same wire type for all electronic signals ie inputs/outputs. The wire in the link is solid core and keeps its shape when bent, also cannot be bent too many times. If you want flexible wire then just choose a multistrand type of the same thickness or slightly thicker. Remember that power supplies eg 5 volt may need slightly thicker wire to avoid voltage drop on long runs

[Fasouli]

The electronics do not know or indeed care what colour wire you use

Logic suggests you use a colour such as black for grounds, and use the same wire type for all electronic signals ie inputs/outputs. The wire in the link is solid core and keeps its shape when bent, also cannot be bent too many times. If you want flexible wire then just choose a multistrand type of the same thickness or slightly thicker. Remember that power supplies eg 5 volt may need slightly thicker wire to avoid voltage drop on long runs

is this good ? https://www.modmypi.com/multi-strand-wire-blue

[fordgt40]

It is the same thickness and is multistrand - so yes