So I bought a used powerchair

[Burgerman]

Yes, but without 4 pole motors you may burn up brushes etc. If you have 4 pole already, then go on ebay and buy a 120 R-net and dont pay more than 125.

Will you feel a difference? Depends. Do you ever run out of torque or exceed 90A at the motor?

Run the R-Net software, and WATCH as you do curbs, threshholds, turn in place on carpets, ramps etc.

See here

M1 and M2 Amps as I zero turn sharply in my hallway.

[LROBBINS]

Probably not much if any - the DX90 also has a short-term boost current. What might make a bigger difference, if you haven't already seen to it is heavier wires in the battery-to-PM loom and from the PM to the motors. I don't know about your chair, but some manufacturers skimp on this - even not increasing motor wire size if over xxx mm long as Dynamic specifies. If you do put in heavier wires, reduce motor compensation a bit and then tune it - with lower total resistance things might get a bit snappy if you don't reduce compensation.

[Burgerman]

Actually the R-Net 60, 80, 90L can only do a Max of 60, 80 or 90A respectively and no boost current at all.

The R-net 120 is actually a 100A unit, that can do 120A for a few seconds at a time as a BOOST current, and thats usually all thats ever required.

So the PM120 has 10% more all the time, and a quite large 30A per motor higher current for up to 10 seconds when needed than the PM90. Thats quite a large difference, it equates to a 25% greater torque. And current.

Swapping a PM90L for a PM120 is very noticible, IF you use that much current. By which I mean programmed to go, stop, turn when you tell it. If you dont use more than say 80 to 90A then it will have zero affect on your usage. Until you want to dig yourself out of a hole... Climb a curb, etc.

Another example. A pilot plus 80A on the old F55 was swapped by me for a 100A unit, and it made a chair that previously wouldnt wheelie, lift the front wheels with ease. Turned it into a monster! Same for curb climbing. And thats only a 20% gain. Had it been programmed less aggressively, it would likely never have felt much different.

[Irving]

Handicare spec'd different motors for DX vs PG (see parts list posted above). I'm guessing the difference is motor resistance/stall current? What will that mean on setup going to RNet from DX? Just motor compensation setting?

[Burgerman]

IF its different yes. But its more likely just different connectors. Or brake voltages. Most 4 pole are best set at 45 to 50mOhm.
Most* 2 poles are the SAME motor with 2 brushes missing, and same armature. And 2 magnets are missing. So they are usually cheaper and double the impedance. So 90 to 110 mOhm. This makes them way less efficient. But they dont care.

* Some recent 2 poles like the chinese Linix motors are NOT just 4 poles with missing parts. They use a longer armature/casing, and are around 2/3rds as powerful as the 4 poles. And impedance matches. at round 60 to 70mOhms depending on specific motor types.

[Irving]

Ah yes, I knew and forgot about connectors. Makes swapping from 90A DX to 120A RNet less plug & play... Not impossible but a PITA.

[Burgerman]

What overboost does DX 80 allow? If its a lot (lenny says it has some) it may not be worth it. Non as far as I can find.

https://dynamiccontrols.com/sites/defau ... issue1.pdf

There is dx that has 120A boost for 1 second. Thats a 90A unit I think?

[Irving]

Here's a thought...

If I was planning on buying a Puma40 (or possibly any other similar chair) and I couldn't find an RNet version at a sensible price, would it be sensible to consider a 90A VR2 simply because the motor cables are the same as RNet so making the later conversion easier/possible?

[Burgerman]

If the cables are also large enough. Or you might want the battery cable to module loom too.

[LROBBINS]

John,

Per your comment

There is dx that has 120A boost for 1 second. Thats a 90A unit I think?

Terry2 has a DX90a

Would a R-Net 120ah make any difference over my dx2 90a?

[Burgerman]

dx90 already has 120A boost capability. If programmed to do so. So no difference. I have one here.

Hence viewtopic.php?f=2&t=8998&p=142288#p142264