Hi all,

I had an EVT solar geyser installed January 2021 Nd along with it Geyserwise controllers for this and another geyser. Last night around 9pm I started switched on the kitchen (solar) geyser when my wife complained the water was cold. This morning the Geyserwise panel is dead. Consumption on Solarman shows it started momentarily then off. Is this a common occurrence? And best way to fix it? Worth calling the Geyserwise number on the panel?

OK .. some basic fault tracing done. All cables are in tact and the TSE power supply has 230V on L1 and L2 but the little LED on the PSU board is dead. DIY PSU replacement or should I pay the call out fee and let the pro's do it?  Where can I buy the PSU ex stock in Pretoria / Centurion / Cosmo City? 

Edited April 6, 20224 yr by Scubadude

I rolled my own using this PSU for princely sum of R43.70 incl VAT. And.... they are in Centurion and have stock 😀 

220V AC/DC Module 12V @ 0.4A - Micro Robotics

This is pic of my repaired unit. 

 

 

Brilliant! Either that or the complete board from Geyserwise for around R400. If the PSU replacement involves soldering I may just go for the board ...

Yeah there is some simple soldering to do. The 220V from the TSE board goes to the new PSU via the grey and blue wires. 

The 12V output are the 2x red wires. The 12V is rectified and smoothed by the diodes and the capacitor to the right of the new PSU. These are not needed as the PSU generates DC  whereas the old one was a simple AC to AC transformer. The voltage then goes to the 7805 mounted on the heatsink that you can see in the top right hand corner of the pic. 

For R43 you can try it with out costing you too much $$$ -  and if it blows up (and not you) then buy the replacement board. 

OK being time deprived I picked up the board and replaced it ... No joy! LED in the middle still dead. Control panel still dead. Now what?

Suppose the board could be a dud but what are the chances?

Edited April 8, 20224 yr by Scubadude

On 2022/04/08 at 6:49 PM, Scubadude said:

OK being time deprived I picked up the board and replaced it ... No joy! LED in the middle still dead. Control panel still dead. Now what?

Suppose the board could be a dud but what are the chances?

Are you getting 220V going to that box ? Try unplugging the LED control unit and see if the middle LED lights up. Maybe the LED control panel  is blown (or something else) and is a short circuit which would pull down the 5V which drives the LED (I think) or pulling down the DC going to the 5v regulator. Or maybe the fuse has popped ?

This is what mine looks like without being plugged into anything. Ignore the top left red LED, that is on the replacement PSU board. 

 

Fuse is intact on both PSU boards - silly me I should have checked that first of course. Unplugging the leads makes no difference.  One thing that looks odd is I get +/-230V between L and GND, and the same between N and GND, but 3 or 4 V between L and N.  Is that right?  Even if it isnt, it was like that since I had the geyser installed in Jan 2021, or as a minimum since the ocmpletion of my solar installation in December last year.   

Edited April 10, 20224 yr by Scubadude

OK, so I tested the old PSU board with a plugged cable and it is working.  So now either something in the wiring between the DB board and the PSU changed (unlikely) or something on the geyser has side changed. I'm at a complete loss here ... anyone have any ideas what to test next? 

19 hours ago, Scubadude said:

One thing that looks odd is I get +/-230V between L and GND, and the same between N and GND, but 3 or 4 V between L and N.  Is that right?

That's not right , but certainly possible , in fact it's a giveaway that your neutral wire is faulty, ie disconnected somewhere .  Because this neural is now floating , you will measure 230v to ground , and you will measure a small difference between live and neutral ( the live enters the PSU transformer , leaves the PSU at the neutral , but because no input current is flowing , neutral will be at live potential !)

So you need to trace that neutral wire / connection. 

Edited April 11, 20224 yr by BritishRacingGreen
Extra info

16 minutes ago, BritishRacingGreen said:

So you need to trace that neutral wire / connection. 

This type of fault is a prove that a neutral is as unsafe to touch as a live. A floated neatral is dangerously masquerading as a live, so please take care when debugging.

Thanks BRG! I'll trace it tonight ... there is only the trip switch and isolator in the circuit.  But what could cause this to change all of a sudden after months of faultless operation?

Well spotted @BritishRacingGreen ... fried neutral in the main DB. I'm no electrician but clearly the one that wired this board wasn't one either - didnt even bother to secure the wire. Will fix it in the morning when the wife and kids have gone out for the day.

And fixed. Upside is I have a spare TSE power supply board if anyone has a need for it ...

@Scubadude brilliant ,  all is well that's ends well . Dry joints on   neatral busbars are invariably cause of many and ugly problems .  Especially when loads are significantly high like geyser.