Opencockpit FWD Overhead KIT

[biggstuff]

Good day fellow enthusiasts.
I received my ordered FWD overhead KIT from OC.
I am lost as to how to wire this up and the manual is not very explicit as to how to go about it.
Does anyone here have the experience or some idea on how to wire this up? Some video or pictures would be great
Much appreciated for any help.

[NobbyC_B738]

Hi,
I have done the FWD OVH wiring completely on my own so I may be able to support you.

Prior to any wiring activity you should think about the numbering and how to arrange the OC cards.

Software related issues:
The numbering on the OC mastercards is clearly defined for inputs (e.g. switches) and outputs (e.g. annunciators)
Regarding wiring you have two options
a) Use same numbering system as we have it in Roar’s PMDG B737 scripts
b) Use your own numbering system and adjust assignments in the script

Advantage of a) is that you need less script adustments, especially helpful when trying new scripts
Advantage of b) is that you are more flexible in wiring. Inputs are organized in groups (9 inputs with one common ground contact). So if you want short and clear wiring it’s a good idea to put inputs together that are located close together and have similar functions. Input connection cards can then be located close to 4 of these groups (4 groups x 9 inputs = 36 inputs for each 40-pin-connector J3 or J4)

Additionally for clear overview I have created an excel spread sheet, that indicates what function is on what connection and what is the corresponding SIOC variable
This spread sheed proved to be very helpful for all my software tests, individual modifications and troubleshooting

assignment1.jpg (251.79 KiB) Viewed 2647 times

Hardware related issues:
As this is a software support forum and not a cockpit builder forum I will not go into details here. For easy wiring I can recommend to use OC input- and output connection cards. Additionally I have installed a kind of second “deck” over the panels to have OC electronic cards very close to the panels and to have clear wiring. If you like this and need more details or pictures, please advise your Email address or ask Roar to send me your Email address when you don’t want to make it public here. I will then send information directly.

OVH1.jpg (246.39 KiB) Viewed 2647 times

OVH3.jpg (254.09 KiB) Viewed 2647 times

[biggstuff]

You are going to be my savior here.
Did you choose the wire colors at random or there is a meaning to them?
I am gonna need some further explanation on your spreadsheet too
I have PM you with my email address.
I have been so confused since I received my kit, but this gave me a sigh of relief.

[NobbyC_B738]

Yes I chose colors at random. The only meaning is fast finding on the input connection cards and less confusion when taking panels off and putting them back in place after maintenance or after modification.
I bought sets of 0,25 mm² wires with 11 color. I always used “black” on ground and I tried to use 9 different colors on each group of nine inputs. Sometimes I wasn’t consistent because I did some changes later in the groups of nine
It’s a real challenge to find the optimal wiring because only few of the single OVH panels have exactly 9 inputs. In most cases you have to combine e.g. 7 inputs from one panel + 2 inputs from another or 6 + 3

2 examples
a) Left lights panel (my inputs 9 to 17) es easy to wire because you have 7 lights + 2 APU (OFF / START) = exactly 9 inputs on one single panel.
b) Fuel pumps Panel has only 7 inputs (my 0 to 6). So I added 2 further inputs GRD PWR ON / OFF (my 7 and 8) from another panel that is located close to the fuel pumps panel

assignment2.jpg (126.99 KiB) Viewed 2617 times

I did lots of modifications because I added some parts of AFT OVH later to my FWD OVH. For any modification or maintenance different colors proved to be very helpful.

For your understanding a picture of my custom OVH with an own created frame hanging from the ceiling as part of my low budget home cockpit without any OC structure or shell.

FWD OVH with parts of AFT OVH.jpg (236.33 KiB) Viewed 2617 times

I have received your PM and will answer all further questions on this topic directly by mail

[biggstuff]

This is so helpful you will not believe how I am able to breathe now.
However, I had some questions about the spreadsheet with the M1/J3, M1/J2 etc.
What is that representing?
Also take for example below from the script

"Var 2646, name sFUEL_P1_Aft, static, Link IOCARD_SW, Device 30, Input 27"

Does this mean that I would connect a wire from the fuel switch "ON" side of the switch to a number '27" in the OUTPUT card? I am assuming there is actually a number 27 on one of the cards.
In that case what happens to the "OFF" side of the same switch. do I leave it not wired?

I really like what you have achieved with that panel without using OC frames. I will look forward to your email and if you can also attach your spreadsheet for me to use if you do not mind.

[NobbyC_B738]

M* is for number of mastercard
J* is the 40-pin connector on the mastercard

M1/J3 = Mastercard No.1 / connector J3 -> what is an input connector
M1/J2 = Mastercard No.1 / connector J2 -> what is an output connector

Your statement regarding Var 2646: yes and no:
following Roar's original script (and I think it's identical to factory built FWD OVH) fuel switch must be connected to number 27 of INPUT connection card - not OUTPUT card !!

following my spreadsheet fuel switch must be connected to number 0 of Input connection card and additioanlly script must be changed to

"Var 2646, name sFUEL_P1_Aft, static, Link IOCARD_SW, Device 30, Input 0"

As I told you previously you can follow Roar's numbering, or mine or your own. Correct assignment has to be done in the script

You will get a mail within some minutes with more explanation

[idj4]

Hi.

I will try to help too as I have built a FWD OH kit as well. I kept my build the same as the factory assembled Overhead.

As Norbert has previously mentioned, you can choose your own wiring or keep it factory standard.

If have a document that I got from OC, which helps with the Overhead build. It's a 4mb PDF file, but it's too large to attach here. I can send it to you if you would like? It lists all the input/output numbers that the wiring should connect to if your building it factory standard. It also tells you if a connection is an input (switch) or output (annunciator). Here is a picture of the rear of my Overhead.

Regards

Ian

[biggstuff]

Good morning and thank you for your desire to help. This would be very much appreciated.
Norbert has been extremely gracious and extremely helpful.
I have almost made all the ribbon cables and had wondered how to connect the OUTS card. But I see Norbert's and your picture how it's jumped. I definitely missed that one.
I have DM you my email address as well.
So grateful for all the help I am receiving!