Design Weakness

The mounting brackets that hold the digital display on the ebike handlebars has failed again.  Twice I’ve attempted to repair the break in the mounts and both times the mounts have failed in a different location.  I believe it’s a design weakness.

Not wanting to spend the $100+ purchasing a new display I searched online to see if it was possible to buy replacement mounting brackets.  I thought this might be optimistic but to my surprise I found a seller on Aliexpress.   However the price of the brackets was $12.97 with an additional shipping cost of $18.23.  Did I really want to spend that much money on something that was likely to fail.

After  30 minutes of searching I thought I might have an alternative.   A seller on Aliexpress had CNC machined aluminium motorbike brake hose mounts and the hole for the brake hose looked very close to the size I required to mount the display.   Moreover the cost was $12.67 with free shipping.  I took a gamble I could make them work and they were delivered today.

You can see where I have attempted repairs on the original mounts in the photo below

After searching through all my ‘stuff that might be useful one day’ for something that might be used as a 10mm dowel in the hole of the new brackets I realised I could probably use the ends of the original brackets.

Below is how I plan to modify the new brackets.

I cut off the ends of the original brackets and then filed them down in diameter in order to fit them into the 10mm hole in the new brackets

Next I did a test fit

All good.  Time to remount the display on the handlebars using the new brackets.  I don’t think these brackets will break as easily as the originals.  AND they were cheaper!

Well that didn’t work!

Several years ago my brother mentioned his swimming pool involved a considerable amount of ongoing money and effort.  So when Jan said she would like a swimming pool I insisted on the components being both over designed and the best available.  This cunning plan would ensure the pool was almost free of maintenance.

Well that didn’t work.  Every Saturday I find myself brushing down the pool, cleaning the filters, sending Nemo for a swim and testing the chemical levels.  Then the expenses started to mount.  Components needed replacing.  First the filter.  Then the Chlorinator.  Then the Control Box.   Recently the pool robot.   Today it was the UV water sanitizer.

The ballast and UV lamp in the sanitizer had failed.  I hadn’t realised the lamp required removal and cleaning every six months.  The Ballast is quite small.  It’s actually a power supply.

The new ballast (black & green box below) is significantly larger that the original.  Don’t ask me why.

I needed to make a mounting plate to fit the ballast to the wall of the workshop.

After four years of pool ownership the only original parts are the actual pool and pipework.

On reflection some money might have been saved if I’d opted for cheaper components.

Trickery

Two nights ago I had one of those Archimedes moments regarding our DIY swimming pool heater.   To recap.  I’ve previously mounted two second hand solar water heater panels and a photovoltaic panel on the workshop  roof.

The water heater panels are connected to the pool pump with the input immediately after the filter and the output to the return pipe after the chlorinator.  Because heat rises the input pipe connects to the bottom of the panels and the output to the top.  The strength of the pool pump isn’t sufficient to circulate the water through the panels.  Instead the solar panel provides the power to a 12V water pump connected into the input pipe.

The solar panel produces approximately 27V, which is too high for the pump.  To rectify this the panel is connected to a small and cheap solar controller.  The controller has six terminals.  Panel input (+ & –)  Battery (+ & –)  Load (+ & –).  The output from the panel goes to the controller Input and the pump is connected to the Load terminals.  But the pump isn’t directly connected to the Controller Load terminals.   That would result in the pump running continuously whenever the panel received sunlight.  This wouldn’t allow enough time for the solar water panels to heat the water.  To solve this, the Load terminals are connected to a digital timer and the timer controls a 12V relay.  The latter is required because the digital switch is not sufficiently powerful to accept the required power to run the pump.

The 12V water pump is in the grey box and the controller, timer and relay in the box with the window

The solar controller is the orange box at the top of the window.  The timer is displaying 24 minutes until the next pump activation and the red arrow to the relay.

Through trial and error I have identified if the pump runs for a minute every half hour the water in the panels gets hot. 

However the system wouldn’t work.  I’ve since discovered the solar controller requires a 12V battery to be connected before it will send power to the Load terminals.

My ‘Eureka’ moment was when I realised I might be able to trick the controller into thinking a 12V battery was attached by making one from three of my old lithium cells I recovered from a tool battery I found at the rubbish tip.

I made a temporary system to check my theory.   AND it’s currently working!  I won’t make the system permanent until I’m satisfied it’s a long term solution.

Interesting Day

It has been an interesting day.  A clear blue sky first thing which went to great and then heavy rain by mid morning.

Jan is very pleased with her front garden which is currently a riot of colour.

It’s hard to recall this was once a scrubby piece of land containing a boring lone gumtree.

She also planted daffodil bulbs in all the tree rings and with the onset of spring they have flowered.

My main activity for the day was to observe the installation of our new residential house battery.   Three of the existing north facing solar panels are being moved to the west side of the roof and connected to the existing array

The remainder of the north facing panels (shown below) are being removed and replaced with ten new 440W panels.  I’m keep the removed panels.  They are rated at 275W and I’m thinking of installing them on the workshop along with the original inverter.  They could possibly be used to power the swimming pool. 

To be removed

The new inverter is rated at 10kW which is twice the capacity of the one it replaces.  It also has a maximum of four solar array inputs.  We currently only have two arrays and I’ve been looking at where we might install a further two.

There is only one suitable tiled area on the roof.  However it’s rather small.

I could probably only fit three panels here

The other location is the steel section of patio roofing which faces north.  I could potentially have eight panels fitted here which would give us another 3.5kW

The battery wouldn’t fit in the planned location in the garage.  The supplier said it would but didn’t realise there was an adjacent door.  I opted to have it located on the opposite garage wall.

 

It’s a Sigenergy, Sigstor modular battery.  I opted for four 8kWh stacked modules giving us a total of 32kWh of storage.  Hopefully it will store enough electricity to keep the house supplied for 2-3 days.