Geekzone: technology news, blogs, forums
Welcome Guest.
You haven't logged in yet. If you don't have an account you can register now.

9 posts

Wannabe Geek

# 205414 12-Nov-2016 09:09
Send private message

Let me try and explain the setup. I've got a gate opener logic board that has a 12v output for accessories. It has a terminal labelled 'swipe card' that is used to trigger the motors by an accessory. If I use a wire to connect the COM output for the accessory and this terminal it triggers the gates to open. The keypad has a normally open and a Normally closed output along with a shared COM. So if a correct code is put in the normally open output will switch to 5v for 3 seconds and the normally closed will drop from 5v to 0v for 3 seconds.

I had assumed that I could use the normally closed output and connect that into the 'swipe card' input and it would see the voltage drop, but it doesn't.

I could use a small DC 5v to 12v transformer if the logic board is expecting to see a greater voltage drop, but it doesn't make sense to me that I can trigger it by connecting directly to the common output... so nothing connected to the terminal but then grounding it - which doesn't seem the same as a constant 12v going to 0v.

Any digital electronics experts here that can tell what is going on from my limited explanation?

And before anyone asks, these were both bought from China with very poorly documented instructions which have not enlightened me at all!

Create new topic
76 posts

Master Geek

  # 1668424 12-Nov-2016 09:54
Send private message

If I understand you correctly, connecting the common on the gate opener to the trigger on the gate openeer works. So can't you just use the normally open terminals on the card reader to do just that ... i.e. commom to common and normally open (NO) to triigger?

9 posts

Wannabe Geek

  # 1668430 12-Nov-2016 10:16
Send private message

Yes, that's right re your understanding, but no it doesn't work if I connect NO and Ground. Although in the instructions with the keypad it shows the three wires (yellow, black, red) as Power off Unlock(+), Ground line and Power on Unlock (+) and I'm assuming the red power on unlock is NO - is that right?

Does it matter that these are 5v instead of 12v?


76 posts

Master Geek

  # 1668435 12-Nov-2016 10:27
Send private message

I expect that something marked Normally Open closes a dry contact relay ... i.e. no "wet" voltage on it ... a multimedia should see those contacts short togther when triggered ... so no, voltage should not matter, or be involved at all. Are red, black and yellow the only connections on the keypad? That would normally indicate you should power it with red & black and use yellow as the trigger ... how exactly is it marked?





9 posts

Wannabe Geek

  # 1668438 12-Nov-2016 10:36
Send private message

There is another red and black marked as 12v power input. So I have the red lead of that one coming from a terminal marked vcc on the opener that is outputting a constant 12v. The black lead to that one from COM on the opener. A red lead from the 'power on unlock' of the keypad back to the swipe card trigger terminal on the opener and a black lead from the ground of the keypad outputs to the same COM on the opener

76 posts

Master Geek

  # 1668446 12-Nov-2016 10:45
Send private message



So don't you want power off unlock connected? i.e. pull the trigger input of the opener to ground just as you do when you trigger it manually? Just put a meter between the common and the two outputs of the card reader and see if one shorts ... and use that :-)

Create new topic

Twitter and LinkedIn »

Follow us to receive Twitter updates when new discussions are posted in our forums:

Follow us to receive Twitter updates when news items and blogs are posted in our frontpage:

Follow us to receive Twitter updates when tech item prices are listed in our price comparison site:

News »

Microsoft New Zealand Partner Awards results
Posted 18-Oct-2019 10:18

Logitech introduces new Made for Google keyboard and mouse devices
Posted 16-Oct-2019 13:36

MATTR launches to accelerate decentralised identity
Posted 16-Oct-2019 10:28

Vodafone X-Squad powers up for customers
Posted 16-Oct-2019 08:15

D Link ANZ launches EXO Smart Mesh Wi Fi Routers with McAfee protection
Posted 15-Oct-2019 11:31

Major Japanese retailer partners with smart New Zealand technology IMAGR
Posted 14-Oct-2019 10:29

Ola pioneers one-time passcode feature to fight rideshare fraud
Posted 14-Oct-2019 10:24

Spark Sport new home of NZC matches from 2020
Posted 10-Oct-2019 09:59

Meet Nola, Noel Leeming's new digital employee
Posted 4-Oct-2019 08:07

Registrations for Sprout Accelerator open for 2020 season
Posted 4-Oct-2019 08:02

Teletrac Navman welcomes AI tech leader Jens Meggers as new President
Posted 4-Oct-2019 07:41

Vodafone makes voice of 4G (VoLTE) official
Posted 4-Oct-2019 07:36

2degrees Reaches Milestone of 100,000 Broadband Customers
Posted 1-Oct-2019 09:17

Nokia 1 Plus available in New Zealand from 2nd October
Posted 30-Sep-2019 17:46

Ola integrates Apple Pay as payment method in New Zealand
Posted 25-Sep-2019 09:51

Geekzone Live »

Try automatic live updates from Geekzone directly in your browser, without refreshing the page, with Geekzone Live now.

Support Geekzone »

Our community of supporters help make Geekzone possible. Click the button below to join them.

Support Geezone on PressPatron

Are you subscribed to our RSS feed? You can download the latest headlines and summaries from our stories directly to your computer or smartphone by using a feed reader.

Alternatively, you can receive a daily email with Geekzone updates.