Category: Uncategorized

So following on from my previous post about switches, let’s talk about Passive Infra Red (PIR) sensors.

Loxone Presence Sensor

Cost: OMG HOW MUCH?!
Summary: No way in hell I’m buying one at that price
Supplier: Loxone

Wow, the price of this is staggering. It’s got a light level sensor and a PIR in it. I’m not going to buy one, but I’m including it here without much comment.

Manufacturers site – http://shop.loxone.com/enuk/presence-sensor.html

Generic presence sensor

Cost: Low (£10)
Summary: Not quite what I’m after, but I can hack this.
Supplier: Low Energy Supermarket Ebay shop

I purchased this with the thought that I would place them in some rooms outside of the automation system like the toilet and possibly the kitchen. I ran it in the kitchen for a while until it finally started to annoy me. There’s an adjustable timer and light level sensor which means that once the light drops below a certain level the PIR will activate the light until no presence is detected and the timer runs down. It’s 240v mains, which isn’t great for working with, so having gotten annoyed with it and removed it (Claire nearly cut herself after the lights in the kitchen went out) I took it apart for a looksee.

So what’s the black tube? It’s a fuse, that’s a good thing. Otherwise not much of interest.

Oh hello! That’s a 24v relay. That means that we’re looking at a 24v DC supply. *grin* The Loxone kit is 24v DC, which I don’t think I’ve mentioned so far. The two circuit boards are a mains power supply and the combined PIR and logic board with the two variable resistors on. Removing or modifying the back board *should* give us a board that we can power with 24v and will trigger a 24v line when activity and suitable light level are detected.  We don’t actually care about the light level or the timer so we can turn both right down. Now we have something we can connect directly to a Loxone digital input and feed into a lighting controller block for a fraction of the cost of the official presence sensor.  This I like 🙂

Purchased from Low Energy Supermarket Ebay Shop –http://www.ebay.co.uk/itm/230776895665

Hacking the generic PIR

Some time after writing the top half of this post, I got to the testing.  Tests on the generic PIR revealed that indeed it was 24v as expected. A simple full wave rectification circuit with four 1N4007 diodes, a couple of capacitors, a signal diode and a couple of resistors.

Turns out the signal diode was mostly redundant as far as I can tell, it’s included to eliminate back EMF but that’s actually dealt with by one of the power diodes without need for it. Eh, I put one of the power diodes back in and removed the signal diode.

So testing! Lets see what the current consumption is like on this after the modification

Huzzah! 24v DC PIR with low current consumption and low cost. Our terminals are now switched 24v DC, 0v and +24v DC enabling us to use this on an input as suggested above. The input can then be mapped to the sensor input on the lighting controller and programming via the Loxone as documented.

I’m very happy with this money saving hack and will be buying a few more of these sensors in the very near future!

The Space in Lancaster has acquired a second 3D printer that can be used by Members who have completed the 3D Printing training. This machine is the property of Mark Keating who is allowing use of the machine by members as long as they pay for the costs of the material that is extruded.

The printer is a model of the Replicator 2 and has twin nozzles. This means that it can be used to print with two different maetrials at the same time and can utilise a variety of printing techniques. It should be possible to combine elements such as hard filament and ninja flex to print wheels with tires in situ on a single run.

The printer will take PLA and ABS and is being tested with other materials. It can also handle support material allowing for more complex prints to be achieved.

At this time Mark and Tom are calibrating and testing the printer, they will soon add a part cooling mdification which will further enhance the machine and will be looking to add a glass bed.

The Directors of the Lancaster and Morecambe Makers have today published a ‘Code of Conduct’ to the website that will also be posted in the Lancaster ‘Space’.

There are strong reasons to set a basic code for behaviour in shared spaces and to announce in advance what measures can be taken to respond to any potential incidents. This is particularly true for the ‘Space’ as we wish to encourage younger members to attend and to make the ‘Space’ available to all sections of our society.

We’d ask all members, visitors and guests to be aware of the Code of Conduct which is based upon a principle of respect.

Great companies start because the founders want to change the world… not make a fast buck. – Guy Kawasaki **

The organisers of the Lancaster and Morecambe Makers have made a decision that there should be a Founder Member Donation available. A donation of £100 or more made during the first 3 months of the ‘Space’ 1st March – 30th May makes you a Founder Member for life.*

Benefits of Founder Member: To be honest there are none.

Seriously, none. This is a person who is willing to put money into the space to help us succeed and become financially solvent. members will love them for ever. Their name will be on the roll of honour as founder members. But they get nothing more. There is no rights of access or privileges, they still have to pay to be a member to use the ‘Space’ or pay the day rate/use an open day…

…though there are rumours that there wil be a special badge, and/or plaque, just because they are being so cool 🙂

The current list of Founder Members is:

• Shadowcat Systems Limited
• Mark Keating
• Graham Hill

If you would like to become a Founder Member then please contact us for details of how to make a donation. You contact one of the members (see our About page for lots of contact details or to email us).

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* Though since the organisation is taking memberships now and donations now you have an extra month or so to those dates.

** Read more at http://www.brainyquote.com/quotes/keywords/founders.html#cMtuWYoyCgr5

We had confirmation this week that the Laser has arrived in the UK and will be installed in the space within the next two weeks.

Currently we are looking at the installation to happen on a Sunday, likely the 15th February. All members will be allowed to come along and help fit and receive training on the laser. If you are not yet a member but would like to help out as you are considering joining the space then please contact one of the members (see our About page for lots of contact details or to email us).

The Space will have a number of electronic and manufacturing machines and as more are gained educational courses, training and practical hands-on training will be provided between, and for members. The plan would be to offer these services, access to the machines, and broader technological/manufacturing collaboration between the Space and educational establishments in the district. These will be performed via membership, open days and special ‘education’ days to promote small-scale fabrication.

The Space will also work strongly to promote STEM (Female representation in Science, Technology, Engineering and Mathematics) and build associations with organisations such as the WISE Campaign.  

There is an increasing focus from the government to get more people, especially young people involved in Science and Engineering, hackerspace/maker ecology is particularly geared towards this as this article on the BBC news, from the ElectroMagnetic Field Camp in August 2014, discusses: http://www.bbc.co.uk/news/technology-29011889.