Adding a manual override to door entry system

hi there,

Not sure this is the right place but I'll give it a shot.

I have a simple door entry system wiring details as follows:

wiring diagramPicture of main unitPicture of handset
Also via link:

I want to add a manual door release button, can i do this from the main unit? eg by closing a circuit?

Many thanks!
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xeniumAuthor Commented:
3rd pic is of spare handset hence no wiring showing.
David Johnson, CD, MVPOwnerCommented:
2018-05-19_22-58-31.jpg See your picture 1
EirmanChief Operations ManagerCommented:
To add your manual release (push-to-make) switch, make the following two connections .....

Terminal 1 on the Speaker-Amplifier.
- or -
Trace the black wire from Terminal 1 on the Speaker-Amplifier to the power supply.
Connect to this terminal of the power supply.
(This corresponds to the left hand connection of the power supply in the diagram).

Trace the red wire from Terminal 3 of the Speaker-Amplifier going to the lock.
Connection two is to the OTHER terminal of the lock.
(This corresponds to the bottom connection of the electric lock in the diagram).

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xeniumAuthor Commented:
Thanks, yes i can see the logic from the wiring diagram (with the switch marked as i want it, as David highlights above)

So I guess I'm stuck on connection 2, is there a way to see what that is from my second photo?

OR, do i need to dismantle the lock and do some kind of trace test if it's not clear from the wiring

OR, does connection 2 not even pass through the main unit (which would improve security too), in which case i guess i may need to run another wire. There are spare wires in the wall, hopefully some can get me from the main unit to the lock.

Thanks again
David Johnson, CD, MVPOwnerCommented:
where it has the switch 1 you can run another switch using the same connections as switch 1 ... you can add as many as you want
xeniumAuthor Commented:
From the diagram I believe that the switch is need is to connect from terminal 1 of the main unit to terminal 7 of the telephone circuit.

But since terminal 7 of the telephone circuit does not connect to the main unit, so I'll need to find where i can pick that up from.

I'll assume I need to dismantle the lock to check what wires are there, and if there's any spare that i can run back to the main unit. I appreciate this could compromise security so will need to consider this.

I actually want to put a keypad entry, hence looking at the wiring on the main unit outside. This could be a follow-up question to post.

Thanks again
David Johnson, CD, MVPOwnerCommented:
no just 1 and 3.. in a schematic (wiring diagram a dot means a connection, the switch completes the 12V circuit that activates the relay that unlocks the door.
xeniumAuthor Commented:
hi David, I understand the wiring diagram, it's how this would relate to the routing of wires in the wall i'm not sure about without unscrewing things.

In any case i certainly don't want to connect terminals 1 & 3  that would be a short circuit!
David Johnson, CD, MVPOwnerCommented:
Unless you are the owner of the property it is probably mandatory that you hire an electrician to do the work.
EirmanChief Operations ManagerCommented:
I certainly don't want to connect terminals 1 & 3  that would be a short circuit!
Correct - Note what I said above regarding connection two and terminal 3 .....
Just trace from terminal 3 - Don't connect to terminal 3!

If you disconnect the power from the system, you should be able to use a multimeter in continuity mode, to trace from terminal 3 to the lock.
David Johnson, CD, MVPOwnerCommented:
In any case i certainly don't want to connect terminals 1 & 3  that would be a short circuit!
when the solenoid on the lock is engaged terminals 1 and 3 are connected there is also a solenoid in the circuit that acts as the load.  

You have the current n/o switch you want to add another n/o switch in parallel with it
xeniumAuthor Commented:
Yes I'm the property owner, but good point for others to note - in the UK part P may stipulate a certified electrician.

Between terminals 1 & 3 is the load, so i wouldn't connect 1 & 3 directly as this would be a short circuit.
David Johnson, CD, MVPOwnerCommented:
sorry, connect pin 3 to one side of the switch, connect the other side to the solenoid the same way the existing override switch is wired
xeniumAuthor Commented:
Thanks all.

I had a look at the latch release, there are 4 wires connected to the 2 terminals: black+blue to one (negative i assume) and red + yellow to the other (positive).

See photo attached.
wires on latch release
I guess there are 2 wires to each terminal as this somehow gives provision to split off a switch.

Also the spare wire in the main unit consists of 8 wires: blue black red yellow green brown orange white. See photo.
spare wires in main unit
Tomorrow i'll be able to check the wiring at one of the intercoms, hopefully the last piece of the puzzle. From the photos and info so far i think i should expect to see:
T3 green
T4 brown
T5 yellow, orange, or white, depending on which of 3 intercoms i open up
T6 blue
T7 black or blue
xeniumAuthor Commented:
If there are any spare wires running from the intercom to the main unit, then presumably i can bring T7 from the intercom back down to the main unit, and put a switch between this and T1 from the main unit.
xeniumAuthor Commented:
I have checked 2 of the intercoms, they are both the same:

T3 green
T4 brown
T5 yellow
T6 blue
T7 black
In each there are 3 spare wires: red, white, orange
xeniumAuthor Commented:
I'm a bit stuck on how to bring the intercom T7 to the main terminal. I'll take another look later. I guess i need to check that the 3 spares go to the main terminal, but wandering if the main box has 8 spare wires where would they all be going?
EirmanChief Operations ManagerCommented:
Connect one leg of the external switch to the terminal of the lock, with the BLUE+BLACK wires.
I figure that one of these wires must go to Terminal 7 on the handset.
I also figure that the Red on the other lock terminal goes to 3 on the speaker Amp.

wandering if the main box has 8 spare wires where would they all be going?
There is no way we could remotely answer that query.

To trace spare wires, disconnect the power from the system, and use a multimeter in continuity mode.

You can also trace wires over longer distances with a multimeter in voltage mode
if you have a battery, a length of wire and a few small crocodile clips.
If you don't have a multimeter, use a suitable low voltage bulb or buzzer.
xeniumAuthor Commented:
Thanks all for your feedback.

Sorry got confused with the new EE points system no idea why they changed it, worked fine before.

In the end I sent my electrician in so will post details here if i get them.

I did however find another quite important piece of the puzzle - the location of the transformer and main junction box, opening this finally made sense of the cables!
EirmanChief Operations ManagerCommented:
Once you have access to the main junction box, tracing cables should be relatively easy.

Good luck!
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