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This thread has been started for discussion related to Aussie based builders of DIY 150V 45A mppt controllers, development of which is discussed in an associated thread '... roll your own', so as to avoid clogging up the excellent and advanced discussion in that thread. This is to allow for amateur/novice level discussion of all matters associated with these controllers from theory to build practise. Most current builders are also, ambitiously, building Wiseguy Inverters. Constructive input is invited from expert and experienced builders.
poida Guru Joined: 02/02/2017 Location: AustraliaPosts: 1475
Posted: 02:08am 22 May 2026
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Best of British Luck to you all.
my advice:
1 - obtain a DSO, new ones are reasonably priced and will go a long way in both learning how to avoid blown up FETs and choosing an adequate choke for both mppt and inverters.
2 - a bench power supply or two, such that 50V at 5A is possible. Ones that have current limiting is needed.
choke design is very much "use what you got" but test it to ensure it will work at the power levels required.
3 - make a choke tester. it will use the DSO. and the bench supply. You will discover during testing of the chokes how much power is possible before saturation. In fact, making the tester and using it will develop a large part of the skills needed for all this.
4 - get a decent DVM and leads. make some long leads with alligator clips to suit the meter. this frees up hands to get somewhere safe. Consider also a UNI-T clamp meter that does DC current. We need to calibrate the mppt..
hope this helps.wronger than a phone book full of wrong phone numbers
Dammmit I agree, but also didn't want to hear that! :-), as I and we are beginners. I have a Uni-T Clamp meter: that's a start. We need the power suppply for inverter commissioning, which only leaves the DSO & tester.
That being said, most of the chokes in my haul have already been tested on the other thread and are steel laminate, or we could just buy chokes with established performance parameters.
Am studying the former threads in detail and will make more notes about the tester and methods described there in detail, for now.
Question directed to Revlac re: Aurora chokes. I'm now regretting pulling one of my two 5 kW Aurora chokes apart after seeing one in use, untouched, in your build thread. Not to worry because I have two more 3.6 kW units OTW, there should plenty nuff components there. I can rewind the bare choke as well.
Did you ever test that choke to saturation?
Picc of my choke candidates posted again for reference. I'll proceed with the build without the DSO in the interim, having confidence in my choke parameters.
Revlac Guru Joined: 31/12/2016 Location: AustraliaPosts: 1264
Posted: 08:36am 22 May 2026
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I didn't do a saturation test on the Aurora choke, didn't see the need for it as Poida and others tested and posted results of many chokes (not one of these that I am aware of) these were a little bit bigger cross section than the aerosharp cores and results should be marginally better. I still have one Complete 5Kw Aurora choke and will check it with the LCR tester (if it still works)when I get time tonight or in a few days orso, I need to build another charge controller anyway.
Edit: Ok found something I was looking for, The lab power supply I have is only 30v not relevant but it has a USB power supply to run the LCR meter to test the choke. I have photo's but you will likely do your own later so here are the numbers, The choke as is tested 517uH, now with the loop at the bottom cut One coil measures 157uH then join the 2 in parallel (as in the photo take not of which winding's are the inner layer and outer layer) I get 145.9uH You may wind your own but this is an easy start for a first build IMO. Edited 2026-05-22 22:22 by Revlac
Footnote added 2026-05-23 18:05 by Revlac I used a LC200A tester, old version without the case. Cheers Aaron Off The Grid
- what wattage ratings are specified for the resistors? - What are the hole spacings and max diameters for the capacitors, excepting the large 470 uF capacitors on the main board (10mm/35mm)? I assume these can be obtained from the PCB layouts if not readily available.
Revlac Guru Joined: 31/12/2016 Location: AustraliaPosts: 1264
Posted: 08:25am 27 May 2026
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Capacitor typical lead spacing of 3.5mm 8mm diameter If not sure sometimes you can see typical size components on old Grid Tie Inverter's for reference Edited 2026-05-27 18:26 by RevlacCheers Aaron Off The Grid
Bryan1 Guru Joined: 22/02/2006 Location: AustraliaPosts: 2024
Posted: 09:28am 27 May 2026
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Years ago Poida put up a circuit to test a choke where it used a diode, a cap and a fet to pulse from an nano where a current sensor was put on the add to the scope picture.
Now I don't want to go off topic but my inverter has just gone past 80 Kw Hours and everything in my shed just works like using my mig @110 amps did break the 16 amp circuit breaker so a 25 amp one needs to go in.
As I did have both boards here I just had to try the first one that just works now I am on 24 volts and this MadBoard just works.
Now I did get a price on a 48 volt 600AH forklift battery where 5.5K aint a bad price so that is on my price list so I can power my shearing shed with this chinese Tip Top board that cost me $300.
So plenty of options mate
Regards Bryan
wiseguy Guru Joined: 21/06/2018 Location: AustraliaPosts: 1291
Posted: 02:25pm 27 May 2026
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The electrolytic capacitors on the MPPT power board are 35mm diameter, solder pins are "snap in", the snap in mounting hole centres are 10mm on the PCB. C1, C2 are 3.5mm All the ceramics are monolithic or film and are 0.2" or 5.08mm All resistors are 0.4" or 10.16mm
The resistors are all 250 - 500mW, but R9 & R10 should be 600mW - 1W but the hole sizes are only ~0.9mm so some resistors could be tight. I think for R9 & R10, I used 2 x 22R 400mW in parallel ie bend the pins as if either could insert into the board & solder one in parallel to the other just where the legs exit the body so you insert the piggy backed resistors as 1 part. From memory the resistors ran hot - they were an attempt to reduce emi, if they run too hot try reducing C18 & C19 to 470p but with at least a 63 or 100V rating.If at first you dont succeed, I suggest you avoid sky diving.... Cheers Mike
Notice. New forum software under development. It's going to miss a few functions and look a bit ugly for a while, but I'm working on it full time now as the old forum was too unstable. Couple days, all good. If you notice any issues, please contact me.
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