Ohoof. That definitely could have been worse.
It didn't blow the fuse on the multimeter? I still, in 20+ years of electronics work, have never seen someone pop a fuse in their meter.
Ryobi Zero-Turn Mower SLA to LiFePo4 Conversion - (Updated - Build Complete With Pics!)
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It didn't blow the fuse on the multimeter? I still, in 20+ years of electronics work, have never seen someone pop a fuse in their meter.
I don't know yet I would need a second multimeter to check
Hedges
I See Electromagnetic Fields!
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What model multimeter? What fuse type? ?
Hard to imagine the arc doing that much burning with the let-through of a good fuse. So I'm curious what fuse permitted it.
You can pop out the fuse and check it on resistance scale of DMM.
My Fluke has 11A fuse on 10A range, and 44 mA fuse on 40 mA range.
I once tried to test PV string Isc. With string connected to GT PV inverter input and its capacitors.
I've also tried to test "off" battery current draw of the Sable. Suspecting certain electronics was kept powered on due to gremlins.
The inrush popped fuse. What's needed is a banana jumper or switch shorting out meter while completing circuit, then open the jumper to let steady-state current through meter.
About 10 bucks for each fuse. I recently bought 5x 11A and 5x 44 mA (from a trusted distributor.)
Hard to imagine the arc doing that much burning with the let-through of a good fuse. So I'm curious what fuse permitted it.
You can pop out the fuse and check it on resistance scale of DMM.
My Fluke has 11A fuse on 10A range, and 44 mA fuse on 40 mA range.
I once tried to test PV string Isc. With string connected to GT PV inverter input and its capacitors.
I've also tried to test "off" battery current draw of the Sable. Suspecting certain electronics was kept powered on due to gremlins.
The inrush popped fuse. What's needed is a banana jumper or switch shorting out meter while completing circuit, then open the jumper to let steady-state current through meter.
About 10 bucks for each fuse. I recently bought 5x 11A and 5x 44 mA (from a trusted distributor.)
UltrasoundJelly
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Quick update.
In my search for the best 48v charger for our situation I found this one that should work straightaway with the Ryobi charging receptacle:
alliedlithium.com
Online details are thin, but I spoke with the tech peeps at Allied Lithium. They say it charges bulk at 58v then shuts off, no float. Biggest downside is the price, $345 is steep. Also not thrilled with that bulk charge voltage for longevity.
With all this in mind I finally decided on the AIMS charger mentioned previously and recommended by Will Prowse. Found it here for $239 shipped out of VT:
www.yoursupplystop.com
Biggest downside is that it does have a float voltage. My plan is to put the charger on a mechanical timer to shut off at ~12 hours so it won't be getting constantly topped off. I'm going to just use the EOM cord + plug.
Oh, and I've been top balancing my cells in parallel using a bench supply. Opted to not precharge the cells, which started at ~3.2v. It has been charging for 8 days at this point. Like watching paint dry... but the current is finally starting to drop. At about 3A now. Voltages increased to 3.35.
In my search for the best 48v charger for our situation I found this one that should work straightaway with the Ryobi charging receptacle:
48V EZGO Waterproof Lithium Battery Charger
Allied 48V EZGO Waterproof Lithium Battery Charger 15A. Designed to work perfectly with 48V Allied lithium batteries. Includes 48V EZGO OEM plug to charge in existing golf cart port.
alliedlithium.com
Online details are thin, but I spoke with the tech peeps at Allied Lithium. They say it charges bulk at 58v then shuts off, no float. Biggest downside is the price, $345 is steep. Also not thrilled with that bulk charge voltage for longevity.
With all this in mind I finally decided on the AIMS charger mentioned previously and recommended by Will Prowse. Found it here for $239 shipped out of VT:
CON120AC36/48DC - AC Converter / Battery Charger / Power Supply 36V/48
Features Large charging capacity design (25 Amp for 36Vdc; 17.5 Amp for 48Vdc) charges a 100 amp hour battery in under an hour up to 90% charge Power supply up to 25 amps at 36Vdc or 18.75 amps at 48Vdc Three stage smart charger with variable charging voltage algorithm for maximizing battery...
www.yoursupplystop.com
Biggest downside is that it does have a float voltage. My plan is to put the charger on a mechanical timer to shut off at ~12 hours so it won't be getting constantly topped off. I'm going to just use the EOM cord + plug.
Oh, and I've been top balancing my cells in parallel using a bench supply. Opted to not precharge the cells, which started at ~3.2v. It has been charging for 8 days at this point. Like watching paint dry... but the current is finally starting to drop. At about 3A now. Voltages increased to 3.35.
UltrasoundJelly
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Update on the AIMS charger. I contacted their tech support re: float voltages for LifePO4 and here is their reply:
Nandologist
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I'm new to the forum, not yet involved in the solar power arena but very interested in converting my Ryobi 480e (75ah) to Lifepo4. I've been reading every post on this thread with much interest. My question based on your experiences converting the mower to Lithium and paving the way for the rest of us, how much would it end up costing right now, beginning of 2022, after all is said and done? batteries, bms, charger, new battery meter to replace stock.
right now to change the 4 AGM to the same 75ah AGM is $650 out the door and to upgrade to 100ah is like $770 out the door.
if upgrading to Lifepo4 is twice that price, will they last more than twice the time [years of use] to make it worth the investment? If I use the AGMs to no less than 50% DOD shouldn't they last about 3 years? I know this question is probably not straight cut, but I'm just trying to make sense of the investment without having solar to use the batteries for that use in case the mower dies of other issues (motors or something, mower is already 200hrs old on original Leochs).
thanks!
right now to change the 4 AGM to the same 75ah AGM is $650 out the door and to upgrade to 100ah is like $770 out the door.
if upgrading to Lifepo4 is twice that price, will they last more than twice the time [years of use] to make it worth the investment? If I use the AGMs to no less than 50% DOD shouldn't they last about 3 years? I know this question is probably not straight cut, but I'm just trying to make sense of the investment without having solar to use the batteries for that use in case the mower dies of other issues (motors or something, mower is already 200hrs old on original Leochs).
thanks!
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AMDPower
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@Nandologist I'm not sure where prices are right now but building it yourself shouldn't be twice the amount of money. I ended up spending $1100 vs. $800 for AGM. And I shouldn't need to ever worry about changing batteries again. I would get the use out of your existing batteries but if you have to upgrade down the road, then heavily consider switching to Lithium. If well maintained, I think you will get much, much more than twice the lifespan.
Keep in mind, lithium is 1/2 the weight, getting 100Ah of lithium would be easy drop in replacement around 1200 from plenty of sources and you would have TWICE the mowing capacity of agm for half the weight with DECADES of life.
You could source the cells and build something, around half that, but drop in makes more sense.
There are readymade 48V server rack batts that would work also. Under 1600
You could source the cells and build something, around half that, but drop in makes more sense.
There are readymade 48V server rack batts that would work also. Under 1600
Nandologist
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based on the suggestions, I'm looking at drop in replacements and EG4 is catching my eye, although my wallet says no... but PayPal is having a discount if I buy from them and I just realized they're right here in East Texas. I can save the shipping.... so tempting.
Is EG4 good?
Is EG4 good?
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Will the EG4 fit where the AGM batteries are located?
The EG4 server rack will not fit in the existing battery location in the 480e. It is too wide. There is however a 48V 100AH Water-Proof Bluetooth Battery by EG4 that should fit given the dimensions on the spec sheet. It is a bit more than the base 48v server rack battery but you will have bluetooth to connect to the bms with their app. You won't be able to use the long middle bolt anymore so you will have to come up with another way to hold it down.
icenov
New Member
Still putting the finishing touches on my LiFePO4 replacement (200 Ah) and not in the mower yet, but came across this document while trying to find some info on the wiring harness and charging socket. It's called "Ryobi RY48ZTR75/100 Riding Mower Electrical Components Troubleshooting and Testing" - and while it's light on specs, it does have some useful info on the rest of the system in its 50 pages.
AMDPower
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Nice find. Thanks!
UltrasoundJelly
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Just wanted to share a couple 3d prints I made for my battery build that might help others.
First is a mount for the 100A QWORK Battery Shunt Monitor. My model didn't ship with the acrylic holder so I modeled this one after the one that ships with some other-branded shunts.
www.thingiverse.com
Second print is a mount for the Overkill 16s 48v BMS. It includes a slot for the bluetooth module.
www.thingiverse.com
First is a mount for the 100A QWORK Battery Shunt Monitor. My model didn't ship with the acrylic holder so I modeled this one after the one that ships with some other-branded shunts.
QWORK 100A Battery Monitor Mount by UltrasoundJelly
This is a mount for the QWORK 100A Shunt Battery Monitor . There are similar shunts available that ship with an acrylic mount. I modeled this mount after that acrylic mount, as my QWORK 100A did not ship with one. Printed here on Prusa i3 Mk3S using Overture PLA with 0.2mm layer height. I used...
www.thingiverse.com
Second print is a mount for the Overkill 16s 48v BMS. It includes a slot for the bluetooth module.
Overkill Solar / JBD 48v 16s LifePo4 BMS Mounting Bracket by UltrasoundJelly
This is a mounting bracket for the Overkill Solar / JBD 48v 16s 100a LifePo4 BMS. It requires two small screws to secure the BMS to the bracket and four #8 wood screws to surface mount the bracket. There's a slot for the bluetooth breakout board and a loop to zip-tie its cord. Printed in here...
www.thingiverse.com
curiouscarbon
Science Penguin
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BEAUTIFUL JBD MOUNT! ?Just wanted to share a couple 3d prints I made for my battery build that might help others.
First is a mount for the 100A QWORK Battery Shunt Monitor. My model didn't ship with the acrylic holder so I modeled this one after the one that ships with some other-branded shunts.
View attachment 83441QWORK 100A Battery Monitor Mount by UltrasoundJelly
This is a mount for the QWORK 100A Shunt Battery Monitor . There are similar shunts available that ship with an acrylic mount. I modeled this mount after that acrylic mount, as my QWORK 100A did not ship with one. Printed here on Prusa i3 Mk3S using Overture PLA with 0.2mm layer height. I used...
Second print is a mount for the Overkill 16s 48v BMS. It includes a slot for the bluetooth module.
View attachment 83442Overkill Solar / JBD 48v 16s LifePo4 BMS Mounting Bracket by UltrasoundJelly
This is a mounting bracket for the Overkill Solar / JBD 48v 16s 100a LifePo4 BMS. It requires two small screws to secure the BMS to the bracket and four #8 wood screws to surface mount the bracket. There's a slot for the bluetooth breakout board and a loop to zip-tie its cord. Printed in here...
that you post a thingiverse link, completely incredible. thank you for generously sharing ??
UltrasoundJelly
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So it looks like based on page 41 shorting the wire harness across blue (Charger Interlock) and red (pos voltage) wires will result in the green charger light coming on and the mower locking out from moving. Has anyone successfully bridged those and maintained this function using the original charger cable/plug?
Thank you AMDPower for starting this thread. Lots of great info. After reading everything, I ordered the Ryobi 42inch 100Ah zero-turn yesterday. I'm going to be mowing a lot of lawns with it so I needed to know I could replace the batteries and get more run time. Unfortunately I have neither the time or the expertise to build my own battery, but I don't mind paying for a drop-in solution. My question is, if I went with either 4 12v 100Ah in series or the single 48v 100Ah do I need to change the charger, cables, meter and add some kind of cooling or is it a true drop-in like so many of the batteries advertise. I'm a total noobie when it comes to this stuff. I really just need the easiest solution to get more daily run time. I think somebody mentioned that you would have to charge the 4 12v batteries with 4 separate chargers. I'm probably going to replace the batteries right away as I mow grass for a living and I just don't think the stock run time is going to cut it (pun intended). I was looking at the Mean Green mowers which claim a 7+ hour run time but would end up costing me about 13-14k to purchase and get out to Hawaii, so I can easily justify an extra 2-3k on top of the cost of the Ryobi. Any thoughts would be greatly appreciated.
My local home depot has lithium ryobi mower deck new on the lot, 3850...
I find the brushless term used on a mower to be funny...
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AMDPower
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Really?! Awesome! Didn't know they made one yet. Sweet!
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