Sunday, November 18, 2012

Insulate hot parts on outdoor unit of air to air heat pump

Initial opened outdoor unit air to air heatpump showing factory insulation and some extra insualtion added
Outdoor unit, starting to add insulation
There are several hot parts in the outside unit of an air to air heat pump. This heat is basically lost, but most of it can be retained if properly insulated. This advice is valid in climates where the heat pump is used for heating during the winter, and not so often used as air-conditioner during the summer.  After reading about this topic at the Norwergian forum I decided to do this on our Panasonic CS-CE7GKEW. There are claims of adding another 500W additional heat from the indoor unit during cold days. I have a small heatpump already partially insulated, so it might be more like 200W, but it sure will make a good pay off compared to the minimal cost of some insulation.

So I turned off the air to air heat pump unit, and opened up the outdoor unit using a screw driver. Some pipe insulation were already in place from Panasonic, but there were also pipes that were exposed and warm to the touch.
Poking extra insulation inbetween pipes in air to air heat pump outdoor unit
Insulation poking on outdoor unit

completed extra fill up of extra insualtion in out door unit Panasonic CS-CE7GKEW to save energy
Extra inside insulation completed
I got a sheet of insulation and tore off small pieces that I poked lightly in between all the pipes, leaving an inch free at the bottom where there might be water collecting during the winter. Some pipes are cold and do not really need insulation, but adding will also insulate them from cooling the warmer pipes. So I just filled up nicely between the pipes. On the top I added som layers of insulations, but not covering the transformer in the upper left corner of the picture. I do not know, but it might get hot, and electronics are happier when cool. On the right side of the picture you can see that I have also added insulation where the two pipes connect to the indoor unit. The pipes itself do also benefit from more insulation, so I added some there as well, covered by some plastic to keep rain out. I have a roof covering the outdoor unit, so this should be sufficient for weather proofing.

Summary in Norwegian: Utendørsdelen på en luft til luft varmepumpe har mange varme rør som har lite eller ikke noe isolering. Ved å fylle på med isolasjonsmatriale kan man unngå dette varmetapet. Det vil da istedet komme til nytte som levert varme til innedelen.

Thursday, September 6, 2012

Programming the MPIII electric bike controller

What I really like with the Magic Pie 3 motor is that it has an internal controller and that it is possible to program the performance of it using a dedicated MPIII to USB cable. Disconnect the cable on the ebike going to the thumb throttle and plug in the MPIII special USB cable. Then you may download the verson 1.0 of the Personalized Settings Utility, also called PD-280 from GoldenMotor in Canada The problem with this software was that it would only run once on my PC. Starting it the second time I only get this Run-time error '340' message. Fortunately someone at the GoldenMotor Forum have made a version 1.1 that is not crashing. This is the program I ended up using.

And here is my current settings:

I have not found any instruction manual for this so here is mine based on my experience:
Max Current:
This should be taken from your batterypack data. Mine is a GoldenMotor 48V 10Ah LiFePO4. I have probably pushed the limits a bit when selecting 21A and 30A peak. I tried it with only 10A continuous  and it made the bike rather dull with out much hill climbing power. If you use a higher value here your ebike will go faster but you will be loading the batteries more than what they are designed for, and the lifespan of the batteries will be hurt.
Motor type: 
This I have not changed from the factory setting.
PAS Pedal ASist:
I did not manage to connect the pedal assist on my bike, so I am running with out.
Acceleration (or RPM on version 1.0 software):
This sets how responsive the throttle is when you use it. I tried to set this to 40%. When giving max throttle it would take many seconds for the ebike to accelerat to the desired speed. I found 80% to give me the smooth acceleration I was looking for.
Motor Voltage:
Set to your voltage. I have no idea why this was set to 36V in the factory setting. I changed to 48V.
FWD Speed Scale:
This will set the top speed. When set to 100% my ebike makes about 42km/h (26mph) on a flat road. The 80% gives about 32 km/h ( 20mph).
REW: Is probably some way to run the motor in reverse. Not of interest to me.
Regen Break:
When you use the included hand breaks an electrical switch in it will activate the regenerative breaking together with the mechanical  breaks. Set at 50% it gives very impressive breaking power on this heavy ebike. On a wet road or a slippery road it might be a bit too much. I have a long downhill from work to home where I would like to apply regenerative breaking smoothly. I found 10% to fit my taste. Not so much power for fast breaking, but smoother breaking when slowing down a bit on normal downhills.

This is the previous post on how I installed the MPIII on my bike

Friday, August 24, 2012

DIY ebike conversion with MPIII Goldenmotor

I bought a  used  Merida Cruise bicycle and converted it to an electric bicycle with the Magic Pie 3 from Goldenmotor. This is how I did it and a test of the finished ebike.

My initial picture after assembling the Magic Pie 3 and performing my first test run. 
I try to bike to work using my regular bike as often as possible, and then showering when getting there. But some days I have to meet customers, with no option to shower. Then there is also the case when I wake up and just do not feel like pedaling at all. In both these cases I often end up taking the car. My goal now is to keep the car parked, and enjoy life with this amazing ebike.

Since we have many hills in Norway I wanted the bike to have a powerful motor. I found the 1000W 48V MagicPie 3 (MP3) from  GoldenMotor in China. I like the simplicity of the front wheel motor, but decided to go for the rear wheel motor. It gives a better grip and perhaps better handling. I also liked the idea that the controller was integrated in the hub motor. The performance can be tuned by connecting the MP3 to a PC with a special USB cable. A legal limited power motor or a full power bike? You decide by programming.

After about two weeks I got the delivery. There are some special bike tools needed to take off the 6 gear cassette so I went to the local bike shop and got some assistance.
Cassette before adding washer to MPIII Goldenmotor
Cassette before adding washer
Cassette with needed washer for MPIII rear wheel
Cassette with needed washer
MPIII can be used with most 3 to 6 gear bikes. Mine is 6. Take the cassette off the old rear wheel and move it to the MPIII rear wheel. First we forgot the washer and ended up with a cassette that did not free wheel. It was not easy to get off again! So make sure you remember to add a washer that will make the cassette free wheel.
Showing mounting order of washer and cassette on to the MP3 wheel
Mounting the washer , then the cassette
After this I fitted the rear wheel with the motor to my bike and tightened the nuts on each side firmly.The first week I used a twist throttle for adjusting the power to the motor. I did not like it much as I found it too easy to twist. It was also tricky to avoid twisting while breaking. So I changed to a thumb throttle that I like much better.

So on the right side I now have the thumb throttle. It moves nicely with my thumb. I also have the rear hand break from Goldenmotor which includes a switch  that detects when breaking. This signals to the controller inside the MPIII to cut off the motor and activate the regen breaking. The factory setting in my controller was set to 50% regen which gives a good portion of extra breaking power. I have adjusted this to 15% to minimize the risk of slipping. The hand break also activates the original mechanical rear breaks of the bike.

I moved my gear shift from right to left side. That is why the numbers are upside down, but it works just fine. I also decided to not install the hand break with regen breaking on this side. I have kept the original front wheel hand break here, then I can use this for very light breaking with out the powerful regen breaking cutting in. The red button is cruise control. Use the  thumb throttle to achieve desired speed, then hit the red button to maintain that speed. Power to the motor is cut off when hitting the red button again or when breaking with my rear hand break.

The power connector to the battery broke when I was on my first bike trip in March 2013. I fell on my bike when making a turn. I was just barely moving, but the black power connector broke when the bike hit the road. This was at +2C, so it was rather cold. The plastic housing just broke up in many pieces. Seems to be a cold weather problem with this. I replaced it with a original Anderson housing SB50 P/N 992G2-BK. It can be bought several places, such as where it has P/N: 879-992G2-BK
The + and - metal pins from Golden Motor snaps right in to this housing, so it is easy to replace. No resoldering required. If you do cold weather biking it might be good to get a spare now.

Twice I had a flat before understanding the problem. The last time it was obvious. The pressure of the tire was a bit low and when breaking hard the tire and inner tube must have moved slightly. Inside the rim there was a very sharp aluminum edge that corresponded to the razor sharp cut in the inner tube.  In the picture to the left I have sanded it down. Please check for this before putting your tire on the Golden Motor rim.

The performance of the MPIII can be adjusted by connecting a USB cable to a PC and running the free PD-280 software. This is the setting I got when pushing the "factory setting" and then "get config".

GoldenMotor PD-280 software for tuning the MagicPie 3
Factory setting on my MPIII rear wheel motor controller.

I have not been able to find a good guide on how to use this program, so I give you my experience with it in my post Programming the MPIII electric bike controller

Saturday, February 4, 2012

Both LED and CFL have good color in test

Over the years I have been disappointed when buying LED light, but not anymore. Here I have compared CFL and LED as sources for light above our kitchen table.

The light bulbs I have been testing, left to right:
Osram Dulux Superstart Micro Twist 2500K 11W 650lm CFL 10000h 7000on/off Hg=1.4mg 93x42mm
Parathom  Classic A 40  Warm White 3000K 8W 345 lm LED, 
Megaman LED Classic LG0408dv2 2800K 8W 420lm LED 25000h  118x60mm, dimmable 100-10%

I tried one light bulb at the time. My impression using just my eyes was that the CFL had a warmer color and somewhat stronger light than the two LED bulbs. The LEDs gave a very good white light, not like some of the ones I have tried before that was either too blue or too green. My eyes did not manage to see a color difference between the 2800K and 3000K, but so did my camera.

For the pictures below I used my cellphone camera set at a fixed daylight or lightbulb setting. So when the sheet of paper in the picture is white, the color is what the cellphone expect for its setting of lightbulb or daylight light.  All the light bulbs are warmer than daylight, and it is also possible to see the difference between 2500K-2800K-3000K.

2500 K CFL white balance: lightbulb
2500K CFL white balance: daylight
2800K Megaman LED WB: Lightbulb
2800K Megaman WB: daylight
3000K Osram LED WB: light bulb
3000K Osram LED WB: daylight

I walked over to our neighbor, that have a dimer on their kitchen table light, to test the Megman LED that is dimmable. With the particular dimmer they had I managed to dim the light only a little perhaps 100-70%. Not all dimmers work well with dimmable LED lights. Megaman have a good catalog, Professional Lighting Solutions, that explains a lot of different aspects of LED lights. It can be downloaded from