Saipro:


For most "Roy" installations I've seen, installers would use a horrible pair of 4 - 6mm (one for +ve, the other -ve) to run double digit amps over 20 - 50 metres, amongst other blunders. These cables would even have poorly connected joints. Very poor system design can often be blamed. I do agree culprit Roy has poor charging algorithms, no voltage correction and worst of all, no temperature compensation.

bigrovar:

Roy is bad no point calling a spade a gardening tool.

Saipro:
Seen a lot of discussion on the Roy Solar PWM CC over the past two pages. Is the grouse with the brand or with use of the PWM CC (the lines are blurred during the course of discussions)?

My point: for smaller systems (translated as being under 1kW of PV array) with short distance between the array and CC, PWM might be the cost effective way to go (considering Nigeria's climate).

I have 2 PWM CC in my itinerary (Xantrex C60 and Midnite Kid), of which one is in use at the moment for powering my DC security lights and their performance is nothing if not ideal.

Of course, these statements rely heavily on the VoC of the panels and nominal voltage of the system being optimally matched.

nonoski:
Good day house,
Please I have a lot of questions which I will appreciate the gurus to help me solve them.

I currently have 15 panels 3.75kw in 3S5P connection.
My Charge Controller is an Outback Flexmax 80A
My Inverter is a MustPower 5kva (48v)
My battery bank is 400a x 48v

For flexmax 80 the maximum wattage for a 48 setup is 4000 watts

(All connections were done by my humble self)

From my calculation (using the Isc) the 5strings in parallel connection should have around 10.21A x 5 x 1.25= 63.8amps. However the best I have seen from my Log on my Charge Controller is 3.443KWp and 64.1Ap. (See attached Pic)

Would it be wise for me to increase my panels from 15 (3.75kw) to 18 (4.5kw) since it will most time put out about 85% max of its rated power which is about 3900watts and about 76Amps?

The main reason for this is that in Port Harcourt Sun is a luxury. Most part of the day is cloudy and from July to Sept when it will rain for 7 straight days I don wan to depend on phed

2. Another major concern which I’m currently having is that the battery voltage on the Inverter is different from the Battery voltage on the charge controller. Initially they were the same but over time there have been a variance of about 2volts. Should I be worried? I have tried using the Vbatt Calibration setting on my Outback but can only reduce it to about -0.5v which is the maximum I can reduce it to. Picture 2 & 3 were taken at same time

3. My Inverter (Mustpower) shows 100% at when the battery gets to 52volts when I’m using solar to charge, duh its voltage keeps climbing till it gets to about 56.8v (58.8v on the Charge Controller) and drops to 53.6v when the CC gets into float mode. Please is this normal?

Thanks guys for all your help

S007:
I think if used within their boundaries, the premium brand PWM CC will do a good job.
Comparing xantrex, midnite with roy may be like comparing a Mercedes-Benz with keke.

I am considering adding one more rule to my solar rule book. Thou shall not touch anything called 'roy'.

bigrovar:

Egbon you are playing with FIRE. You do not have the battery capacity nor the pv power to be even considering running AC.. Not even for 30 minutes. Limit your battery discharge not just by the 50% did rule, but most importantly by your capacity to replace what as been discharged within the 5 hours sun window (not as easy as you think with Lead acid batteries) that's bulk, and 2 to 3 hours of current limiting absorption and get your battery to float. If you are not careful you will end up in a cycle of energy deficit which would leave your battery in prolonged under charge state (a battery should get full and proper charge on a daily) the beginning of its demise. Save yourself the hassle and get 3k fuel to power our AC for the event. If you have a 3kw solar array then you care dare to dream the AC life. Just my opinion sha.

Saipro:


The price of sustaining sensitive equipment/protecting them from power blackouts/brownouts is the cost of replacing UPS batteries. Next time a UPS dies, replace the batteries, not the entire UPS. Get good batteries to replace the dead ones (Long brand comes to mind). Of course, for each cycle of use, you should endeavour to fully charge the batteries before the next discharge cycle. And don't wait for the UPS to die on you before powering it down; that only kills the battery sooner.

JUO:
Flex max 80a fangpusun 156k
Flex max 60a fangpusun 135k
50a-12/24v 45k. 46k
50aD-12/24v 60k
60a-12/24v/36v/48v 110k.
60aD-12/24v/36v/48v 125k
70a-12/24v/36v/48v 135k with display
45a-12/24v/36v/48v 75k
30a-12/24v 35k
Battery balancer HA02 48v 35k
Battery balancer Fangpusun 24v-25k
MPPT- CONTROL 16K
epever 30a+MT50 12/24v (CN) 50k
epever 30a 12/24v 50k
epever 40a 12/24v 56k
epever 40AN 12/24v 60k
BMV 702 FANGPUSUN 42K
BMV 700 FANGPUSUN 38K
ATS-220V/63A-16K
Watts meter with clock and 50Hz/60Hz
Monitor Analyser 7k
PROGRAMMABLE Digital timer 15/16a 5k din rail
PROGRAMMABLE Digital timer 25a 7k din rail/wall mount
Energy efficient ceiling fan AC/DC '56' 6-36w 25k
080-987-337-09

godspeed:


Thanks bro

In all honesty, deep down, I have always suspected the charge controller.

I have no problems changing it if it is definitely it's the cause of the problem.

Can I be sure I'll enjoy up to 15 hrs (the battery' s full charge capacity )if I get a new charge controller ? Which do you recommend ?

Then, do I really also need to change the inverter too. I think the inverter is ok, it's one of the best out there for home use

Saipro:
Sounds like you might need to invest in an AVS +/- surge arrestor

Saipro:

Congratulations on rolling up your sleeves and getting into the thick of things. That's my preferred route. It also simplifies maintenance and troubleshooting.

I'll attempt to help with my little knowledge base. In order of the questions,

1. You're safer going with ImP rather than IsC in your calculations.
For a place with overcast skies, your instantaneous best recorded (might bel lesser than the best seen) is great. Expect no more and you wouldn't be disappointed; actual NOC values are usually lower ... much lower (assume 73 - 78% of ratings).

Oversizing your array wouldn't be much of a hassle so long as you do not exceed the rated VoC of the FlexMax.
18 panels would be 4.5kWp of PV array. While it might not be the "cost effective" array size (depending on your battery bank size), if it makes economic sense to you, you're alright. Your FlexMax would hardly see beyond 3.5kW from that array size anyway.

2. I'm surprised there ever was a time your FlexMax and the Must inverter ever agreed (except on lower voltages. That, indeed, is an oddity. However, a 2V voltage drop suggests either significant loading of the inverter (based on battery bank sizing, again) or a drift in the calibration system of either (or rarely both) inverter or CC. I suspect you've learnt to place more loads on it even as you've discovered you at times have surplus power generation. A good voltmeter should inform you on which to trust (my money is on the FlexMax again).

3. Mine shows 100% on absorb voltages and 86 - 88% on float voltage (both the 24V & 48V Must inverters). Yours apparently recognises float as 100%. A wee bit preferable to mine but neither is accurate. Do not rely on it, ever. There's more to capacity estimation than mere voltage readings as it dynamically changes with loading percentage. The load % counter/meter is however pretty accurate across all models I've seen. It's the only thing you can really count on - up to around 35 - 50% loading. Right there (and beyond that), the inverter becomes more "efficient" (a paradox). At that point however, some older models might show waveform distortion.

JUO:
@ nonoski if i were you i will use the reading on flexmax

godspeed:


Thanks bro

In all honesty, deep down, I have always suspected the charge controller.

I have no problems changing it if it is definitely it's the cause of the problem.

Can I be sure I'll enjoy up to 15 hrs (the battery' s full charge capacity )if I get a new charge controller ? Which do you recommend ?

Then, do I really also need to change the inverter too. I think the inverter is ok, it's one of the best out there for home use

nonoski:

Thank you
I have reached that conclusion since coz between Outback (Premium brand) and Mustpower I will rather go with Outback

ayinba1:


If you are not sure and you sink another earth rod, and somehow you end up with 2, does it cause harm?

S007:




I am considering adding one more rule to my solar rule book. Thou shall not touch anything called 'roy'.

BLS1:
Hello great house, please I need some advice.

I have been on a 12v backup system for a while with a hardworking used Ritar 150 amp 10hr battery which has served me fine for 2 years with little degradation noticed in performance. No solar just NEPA for charging.

Now I recently got a used 200amp 20hr FullRiver battery, which had been left uncharged for a considerable while ( probably years) but looks in perfect condition.

However once fully charged I noticed a few things about the FR battery: It's float is lower than the Ritar once unplugged ( 13.2 vs 12. and it capacity with load seemed to be only 85% of the Ritar ( I usually disconnect any battery once the voltage drops to 12.1).

Now I have been solely running on the FR for almost 2 weeks now and it does seem its capacity to bear load is improving and float rising slightly ( almost 12.9).

Now my intention has always been to connect both batteries in parallel and use them together. But since it's clear the FR wasn't performing to its best , I decided I would get a desulphator to hopefully get the Float on the FR more in sync with the Ritar before I join them together.

But I read a recent exchange between Oga Niyi and Keikei and i am now wondering if a battery balancer would be a better solution or if it would even work with the 12v parallel system I have in mind??

My main fear is I don't want the Ritar battery pulled down permanently by its supposed elder brother the FR.

Please all suggestions on how best to get the best out of the 2 batteries will be much appreciated.

And kudos to everyone on here as I have gained soo much from all of you already.

pranil:




Although to be fair I am using two ROY charge controllers in my current setup and they are doing their job wonderfully.

....

Keeping the generator starter batteries charged with 20 Watt panels

What did I buy ROY -- Their colours matched my generator body so easy for me to know which CC is charging the gen

And their USB output is also wonderful - I run a Small LED LAMP on them and the Garner is happy charging his phone . What more can you ask for 9000 NGN

NiyiOmoIyunade:
I have used and bought and sold at least 6 different flavors of MustPower inverters - all the ones that I have had access to are very inaccurate with their voltage readings and SoC estimations both under charge and discharge conditions. It is even a wonder how they are able to absorb correctly given the circuit inefficiencies but by my checks they do a reasonable enough job.

Like Oga Saipro said, you should get a decent multimeter to verify the true battery voltage and calibrate the Fangpusun FlexMax CC with that - it comes out of the box pretty accurate but I had a unit once that was 0.7volts off and I was able to offset it by that amount to bring it on point.

nonoski:

It's actually an Outback Flexmax 80A. I go it from US.
I was made to understand that Fangpusun is a Chinese clone (don't know how true it is) duh I couldn't find and reviews of Fangpusun online

pranil:




Although to be fair I am using two ROY charge controllers in my current setup and they are doing their job wonderfully.

....

Keeping the generator starter batteries charged with 20 Watt panels

What did I buy ROY -- Their colours matched my generator body so easy for me to know which CC is charging the gen

And their USB output is also wonderful - I run a Small LED LAMP on them and the Garner is happy charging his phone . What more can you ask for 9000 NGN

pranil:


I beg to differ. T[b]he only way of reliably testing of earth connection is using something called earth megger[/b]

https://www.tester.co.uk/megger-det4td2-earth-tester?gclid=CjwKCAjw0ujYBRBDEiwAn7BKtxVskY0Ebjn7_IDanAUeQ2PbLikI69LuLmSiKQYo8X56c5zYl-vlZBoCPHwQAvD_BwE

- If the earth is even connected by 1.5 mm2 wire the light bulb will light up or multimeter will show low voltage. The earth is supplied already from the disco in a good installation by neutral grounding and hence neutral will always show low voltage with earth.

A good way to check if the Neutral is earthed at home is to switch off NEPA at the entry point ( including neutral) and then measure the inverter output neutral to earth you will be surprised to note that most inverters will show balanced voltage with respect to earth say 110 V ( P to E) and ( 110 N to E)

The higher end inverters have a sperate grounding relay which actuates the main relay ( Victron) or auxiliary contact ( SMA. even newer Ipower models) earth to neutral short on the failure of the grid



That kind of earth is enough to reliably trip a ELCB ( earth Leakage) circuit breaker but may not be strong enough to sink a lightning surge ( or switching surge

typically earth resistance measured ( when isolated from earth bar) should be less than 5 OHMS ( IEEE) , 10 Ohms ( India) 25 ohms ( USA)

In layman's terms during lightning strike, the earth can carry several kiloamperes of current and a high resistance path may raise the circuit potential above 1.5 KV where the normal equipment may fail or people can get shocked

Also there are two values to be concerned with earth Touch potential and step potential. Both concern with human safety. A weak earth can raise a potential along the earth point potentially shocking people on failure of insulation of the equipment



M[i]y advice is to sink one more rod if you are not sure and connect directly to your earth bar with a solid connection without a break -

Typically if the property has large generator e.g. 20 KVA and above you can easily trace and use the generator earth rod as most generator companies will sink a Rod close to the generator and connect to neutral and generator body
[/i]

MAboyarin:
Good morning,

Please, what is the function of "customized" under charger control of Cyber power 1.2 KVA inverter as shown below?

Thanks.

Cc:
kiekie1
GeorgeD1
makavele
pranil
NiyiOmoIyunade
bigrovar
Saipro
JUO
DMerciful
BRIGHTSOLAR

kiekie1:


Good morning MAboyarin,
I havnt really tampered with that setting but with experience, I feel its the usual 10/20a selectable charge current switch , whilst the second is the wide(INVERTER) & narrow(UPS) AC input switch .kindly go through it's manual if still available OR rather get a DC clamp meter and monitor its charge current activity on low battery whilst charging .. I stand to be corrected if their is any user of this same modified sinewave cyberpower inverter in the house ! Cheer's

NiyiOmoIyunade:
I guess the second picture with inverter and batteries in it is your current setup.

Two challenges I see - your current RC 150 meter has an internal shunt (by design this will probably carry no more than 20amps of current safely - at a stretch perhaps 50amps) - you dedicated this RC meter to measuring just your solar power generation but not battery consumption per the diagram.

The new meter has an external shunt hopefully rated for higher amps and hopefully capable of bidirectional readings if you want to measure both amps into the battery and amps out of the battery - I have learnt from hard experience that a meter such as this new one you have rated for 100A should be derated to 50A max when placed in service.

How To Proceed in General... .

Switch off PV input breakers then inverter input breaker

1) Identify the battery and load side of the shunt - in your picture the battery side is the leftmost side with the small black wire connected to the large terminal that has a bolt and nut on it - the load side is the one with the small red wire attached.

2) The way the meter works is to measure the voltage drop across the battery and the load side of the shunt - there is a calibrated piece of metal with known resistance between the two big nuts/screws that have a tiny black and red wire attached to their bases. Those tiny black and red wires are measuring voltage drop between battery and load and given a known resistance (in the shunt) you can calculate the AMPs and or watts flowing from battery to load or from power source (load) into battery.

3) You will need to make a small jumper cable to connect from battery negative terminal to the battery side of the shunt else you bolt the battery side of the shunt directly to the battery negative terminal post if you can. This jumper cable should be as thick as possible and properly crimped

Key to note, the shunt is always connected to the negative cable/side of CC, batteries, inverter

4) Any thing you want to measure through the meter e.g CC amps into battery or inverter amps into battery you place of the load side of the shunt (right side of shunt with small red wire in your picture) - you first switch off the PV and inverter and then trip of DC breakers - disconnect negative terminal of inverter and CC from the battery and attach it to the load side of the shunt (side with small red wire) simply unscrew the nut from the shunt (load side) , connect the lug side of your inverter and CC negative cable through the bolt on the shunt (load side) and replace the nut and tighten.

It will be really long to type all the steps so if you can excuse my abysmal writing and drawing skills, I have attached a diagram that may help you - follow the big red +s for positive cable connections and the big black --s for negative cable connections. Please reach out freely in case of any questions

ebocoms:
@NiyiOmoIyunade
cc @dapsyra

Kindly help check if the attached drawing is OK as described by your steps stated below for the installation of the meter. Also the position of Breaker B.
Thank you.