Finished PTS (Power Transfer Switch)

 Although we got the remote panel for the Power Transfer Switch working at the weekend there was one final part to finish, which is the local panel control.

The 'local panel control' is a switch that replicates everything on the remote panel (switching between Shore Power, Generator and Inverter) so that if there is a wiring fault, in an emergency, you can still operate the switch.

Now it's complete, complete!

Couple of little jobs... AIS and Power Transfer Switch

Completed a couple of little jobs we started yesterday: Finally got the AIS working in both transmit and receive. We're using the Camino 101 connected to our Raymarine chart plotter. Camino AIS equipment can be purchased from our Malu Marine shop.

We also completed installation of the Power Transfer Switch which changes the power from Shore Power to Generator to Inverter. These are also built to order and available from our Malu Marine shop.

High Speed test

We finished the install of the HUI. The punchdown panel, which is still in first generation proved a useful step forward. Doing the first install with this showed up a number of improvements which we'll put into the next version.

The PropEL HUI worked extremely well. It was great to be able to see everything you need (RPM, battery volts and amps, temperature of motor and controller etc) at the helm position.

The new buttons that Tim had sourced made it look really chic I thought.

So what of the High speed tests themselves? Up till now we had only taken PropEL drive train up to about 1,300 RPM (shown on the HUI photo) and we knew it worked well up to that speed but had been reluctant to push it further till we had completely secured the large drive pulley on the prop shaft. The extra washers for that had come with the HUI panel so now it was time to push it further...

At 1,500-1,800 we noticed a speed increase and ability to go into the waves/wind better. We had about 12 knots of wind on the nose for the test and we could push up to nearly 2,000 and get 5 knots of boat speed.

About 2,300 RPM and we noticed a vibration of the mounting which made us decide to investigate before pushing further. This has been our approach all the way along - to take a slow conservative approach to testing, checking out each and every potential problem and fixing before proceeding. The aim is to develop a secure and reliable electric drive that many yachts and boats can benefit from.

With the HUI and throttle now installed and working reliably Tim was comfortable to take King Malu into the marina under PropEL power. The mooring went smoothly despite a 15 knot cross-wind. Afterwards over lunch we talked through the test. One thing Tim noticed was that King Malu stopped and responded very much quicker than with the Honda outboard.

This is what is expected with an Axiom Propellor. We are partnering with Axiom on development of propellors as part of the integrated PropEL system (that's King Malu on the home page of their site) so this was encouraging that their design worked as predicted.

See all posts about PropEL Electric Drive.

Installing HUI and Throttle

Now we have the latest build of the PropEL drive train installed and working the task (apart from extensive testing) is to get all the other components installed and integrated.

I bought some 70/8 lugs in the UK last week as they are not available on the island. We rewired the motor with new 70mm wire and tested… brilliant! We tested for about 3 hours at just over 1300 RPM. There was a bit of a chop on the sea to start with so was useful test.

Today we upgraded the throttle and HUI (Human User Interface) to the latest version.

The throttle was not much different to the previous version. Just adding an LED to show when power was active to the the drive train. Also very slight relocation of the Emergency Stop button to make it easier to press.

This is the first installed version of the HUI for the PropEL project. Up till now we have been using the Distributor/Installer test system as the interface to control the drive train. This works OK for initial testing of the system, but the person at the helm really needs to know the RPM of the motor especially for mooring.

People might think it strange that it's so necessary to have the RPM displayed, after all a lot of diesel motors don't have this. However, you can hear the change in pitch of a diesel motor, the electric drive is so quiet at low RPM that you don't hear anything!

See all posts about PropEL Electric Drive.