frogblender
10 mW
- Joined
- May 27, 2012
- Messages
- 30
Behold, my 450W unite/currie MY1018Z motor, cooled with a blower (a squirrel-cage blower. NOT a fan).
I know there are lots of other MY1018 cooling solutions posted all over the 'sphere, but, effective as they may be, to be honest, they generally look like ass.
This one is compact, effective, and if I'd used a color funkier than white for the plastic, would look great.
THE BLOWER:
The blower is 12v @ .18A. It is fed from my 48V LiFePO4 pack, through a ~$9-on-ebay ~15-60v--downto--12V DC/DC board. The DC/DC is definitely the way to go - too many other cooling solutions power the fan using only one 12v battery within the 36 or 48v pack, which will discharge that one battery more than the other two or three. And we all know an asymmetrical discharge is a very bad thing. The DC/DC is small, cheap, efficient, and so far, reliable. It's draw on the 48v pack is only about 50mA, when delivering 180mA of 12v output.
When the battery pack's power switch is on, the blower is on. I thought about feeding the DC/DC direct from the wires to the motor (so the blower will only run when the motor is powered). The advantages to this would be: a) no blower draw on the batteries unless the motor is producing power; b) silence if you park the bike but leave the battery switch on; c) not having to run another set of wires from the controller to the blower. However, I've since found that the motor needs all the cooling it can get. So having the blower run all the time is definitely the way to go.
I prefer a blower over a fan, since a) a blower is likely to move more CFM than a fan, when one considers the high-resistance tiny-ish holes and tortuous path the air must flow through, and, b) A blower can operate at higher pressure than a fan. A fan may provide suitable airflow when tested in your garage.... but once the bike is moving at 30+km/hr.... the motor is subject to 30+km/hr winds, and funny Bernoulli-like effects may cause a low-pressure-only fan to not move any air at all.... and you'll never know, cuz you can't put your hand over the fan to check when you're barreling along at 30+km/hr.
THE BLOWER MOUNT:
I have access to a CNC mill; The mount is milled out of a hunk of 5/8" or so white HDPE (at least, I think it is HDPE). The blower is screwed onto the mount using wood screws, which self-tap. The mount is screwed to the motor using the unused tapped holes in the MY1018 casing.
The blower output blows towards the rear of the bike, and is angled down a little so any water that gets in there will drain out.
MY1018 MODIFICATIONS:
Drill both plates of the motor housing. What is shown in the pictures are before I redrilled to make the holes substantially bigger. I also drilled a bunch of holes in the yellow FR4 which holds the brushes. I need all the airflow I can get.
Yes, water will get inside during a heavy rainstorm. No problem, because: a) the motor is not usually used in heavy rainstorms; b) any water that does get in will evaporate pretty quickly if the blower is left running once the bike is not in the rain; c) a little bit of water once in a blue moon is not particularly harmful to the motor.
But dang, the motor still gets stinking hot, even with the blower. The blower blows a jet of hot air, so I know it is removing the heat. It may have something to do with my new LiFePO4 52v pack, and the 35A @ 50V I'm driving into the motor. 35A @ 50V is, of course, alot, for this motor. Especially if sustained for more than a few seconds. So yes, I'm still a bit concerned about cooking the MY1018 (that'll be my 3rd cooked 1018). Anyhoo, I'll start another thread on max power into a MY1018....
I know there are lots of other MY1018 cooling solutions posted all over the 'sphere, but, effective as they may be, to be honest, they generally look like ass.
This one is compact, effective, and if I'd used a color funkier than white for the plastic, would look great.
THE BLOWER:
The blower is 12v @ .18A. It is fed from my 48V LiFePO4 pack, through a ~$9-on-ebay ~15-60v--downto--12V DC/DC board. The DC/DC is definitely the way to go - too many other cooling solutions power the fan using only one 12v battery within the 36 or 48v pack, which will discharge that one battery more than the other two or three. And we all know an asymmetrical discharge is a very bad thing. The DC/DC is small, cheap, efficient, and so far, reliable. It's draw on the 48v pack is only about 50mA, when delivering 180mA of 12v output.
When the battery pack's power switch is on, the blower is on. I thought about feeding the DC/DC direct from the wires to the motor (so the blower will only run when the motor is powered). The advantages to this would be: a) no blower draw on the batteries unless the motor is producing power; b) silence if you park the bike but leave the battery switch on; c) not having to run another set of wires from the controller to the blower. However, I've since found that the motor needs all the cooling it can get. So having the blower run all the time is definitely the way to go.
I prefer a blower over a fan, since a) a blower is likely to move more CFM than a fan, when one considers the high-resistance tiny-ish holes and tortuous path the air must flow through, and, b) A blower can operate at higher pressure than a fan. A fan may provide suitable airflow when tested in your garage.... but once the bike is moving at 30+km/hr.... the motor is subject to 30+km/hr winds, and funny Bernoulli-like effects may cause a low-pressure-only fan to not move any air at all.... and you'll never know, cuz you can't put your hand over the fan to check when you're barreling along at 30+km/hr.
THE BLOWER MOUNT:
I have access to a CNC mill; The mount is milled out of a hunk of 5/8" or so white HDPE (at least, I think it is HDPE). The blower is screwed onto the mount using wood screws, which self-tap. The mount is screwed to the motor using the unused tapped holes in the MY1018 casing.
The blower output blows towards the rear of the bike, and is angled down a little so any water that gets in there will drain out.
MY1018 MODIFICATIONS:
Drill both plates of the motor housing. What is shown in the pictures are before I redrilled to make the holes substantially bigger. I also drilled a bunch of holes in the yellow FR4 which holds the brushes. I need all the airflow I can get.
Yes, water will get inside during a heavy rainstorm. No problem, because: a) the motor is not usually used in heavy rainstorms; b) any water that does get in will evaporate pretty quickly if the blower is left running once the bike is not in the rain; c) a little bit of water once in a blue moon is not particularly harmful to the motor.
But dang, the motor still gets stinking hot, even with the blower. The blower blows a jet of hot air, so I know it is removing the heat. It may have something to do with my new LiFePO4 52v pack, and the 35A @ 50V I'm driving into the motor. 35A @ 50V is, of course, alot, for this motor. Especially if sustained for more than a few seconds. So yes, I'm still a bit concerned about cooking the MY1018 (that'll be my 3rd cooked 1018). Anyhoo, I'll start another thread on max power into a MY1018....
