Jump to content

Axpert Inverter Noisy?


Ryanwb1
 Share

Recommended Posts

Im getting my Mecer Axpert MksII inverter system installed on Tuesday.

Some people have said to me its noisy all the time,i figure by noisy they mean the fans.

Others say its only noisy when charging the gel batteries.

I have a small place i dont need a noisy device running 24/7.

Anyone shed some light on this subject?

Link to comment
Share on other sites

9 hours ago, Ryanwb1 said:

Others say its only noisy when charging the gel batteries.

The fan speed control algorithm for the Axpert MKS IIs seems similar to that of the Axpert MKSs. So the fans will run at 30% minimum at all times. Fortunately, this is quite quiet, but it might be annoying in a small dwelling.

The fans respond mainly to load, both inverter load and charging load. So if you're running 75% loads, you'll get 75% fan speed, unless the PV charging is more than this, say 80%, in which case you'll get 80% fan speed. In a 5 kVA machine, the load is calculated as a fraction of 5000 VA, and the charging load is calculated as a fraction of 4000 W. So 4000 VA of load counts the same (75%) as 3000 W of PV charging.

In practice, this means that at night when there is no solar charging and the loads are light, the fan speed will be low, but not silent. The noise will mostly be during the day, when you are using loads or charging the battery, or using PV power to support the load.

So it won't be blasting 24/7, but in a small dwelling, you may want to consider a quieter option.

Link to comment
Share on other sites

3 hours ago, Ryanwb1 said:

Couldn't I just switch the inverter off when not in use if it becomes annoying?switch on again when we are out

I’m not sure on the mecer, I have a clone Axpert the moment it picks up pv solar early morning it beeps and starts charging batteries even if it’s switched off, then again late afternoon when pv is gone it beeps again and then goes to sleep.

It has a alarm ‘on and off’ function but the fans remain the noisy problem.

I once had my inverter inside the house and when it operated on batteries during the night it sounded like having a robot in the house. The fans would rev up and stop and do it’s own thing. The inverter has a silent function when the load is below I think 80Watt than it was completely silent but whenever someone in the house switched on a light somewhere it would rev up the fans. 

I ended up moving the inverter to the garage to solve the problem.

 

Link to comment
Share on other sites

That defeats the purpose as the inverter will be on at times the sun really doesn't shine... I'm assuming you're charging via panels primarily. 

Best option is to keep it in a garage and out of hearing. The 5KVa is loud and annoying.  You can't really dismiss it as background noise as the pitch of the fans changes constantly and makes you always aware of it. When under heavy load they are very loud. 

Also remember that the fans are used to displace heat,  so in a small space this could be a problem. 

I currently have this in my basement and am running over 20 metres of cable to my DB.  Losses are negligible and it works just fine. 

If you have a shaded wall outside you could get a largish plastic container from Westpack and mount it outside and drill holes for the cables to the DB and batteries. 

Link to comment
Share on other sites

I'm hoping it has a power on/off button which completely turns it off...I'm sure it does...I am sensitive to noise and it's going in the middle of my small 2 bed simplex...I will switch it off when I go to bed unless I know there is load shedding...when I get up and leave for work I'll turn it on again

Link to comment
Share on other sites

Three possibilities I can think of. The one is to replace the fans with drop-in replacements that are quieter. I'm not sure how doable that is. Second is put it in a room further away, or install a cabinet outside the house to put it in. Third option, get an inverter with quieter fans, or with the quiet option. For example, the Victron inverters has a firmware extension (aka assistant) that turns off the fans completely. The rest of the inverter works the same as always, so it still switches off at the same temperature, but without the fan sustained higher loads will heat it up faster. This feature is designed specifically for night use in camper vans, caravans and on boats.

Link to comment
Share on other sites

10 hours ago, Ryanwb1 said:

I'm hoping it has a power on/off button which completely turns it off...I'm sure it does...

No, it doesn't. You'd have to disconnect the battery to turn it off. Then you'd need a pre-charge circuit to be able to turn it on again without stressing the inverter and the fuse or isolator. The inrush current is prodigious. [ Edit 2: if the PV charging is the main issue, then arrange for the PV isolators to be accessible; you could turn off the PV till just before you go to work to avoid noise from PV charging. But depending on many factors, the noise may be acceptable until closer to noon, when presumably you are at work most days. ]

5 hours ago, plonkster said:

The one is to replace the fans with drop-in replacements that are quieter. I'm not sure how doable that is.

Weber tried this for one of his customers. It was wonderfully quiet, but there is (or was years ago, maybe it's changed) some issue with intermittent fan locked errors if the replacement fan isn't perfectly compatible.

Begin discussion re replacing fans (Note that the old firmware that caused the fans to run ridiculously fast with tiny loads is long obsolete now).

Original fans put back.

Topic index to find more fan related posts.

Edit: since you are sensitive to noise, I'd say that an Axpert is not for you, unless you can locate it a long way away from where you usually are. But it sounds like it's too late to change now.

Edited by Coulomb
Link to comment
Share on other sites

  • 1 year later...

The 12, 24 and 48v units (pip, Axpert, Synapse, Mercer) all do the same thing. 

If you are floating OR charging the batteries, PV or utility (Eskom) the fans will run at minimum 30% if CPU / Board temp is over 40deg C. If 30% fan speed can get the temp down under 30deg C, the fans will switch off.. (however, temp will probably get back to 40deg C within 20min anyway)

The only time the fans will not run is if you ONLY use PV input, and there is 0v from PV ie, night time, and your load is very low. (This is the same as not charging or floating - and in this state, you are using the batteries)

I have 12 months left of my warranty - in that time, I am going to attempt to write a patch for my firmware to change the upper limit of the fan control (40deg C to 60?) If anyone has experience with the .hex firmware, please let me know? (translations, debugs, ect)

After that 12 months, I am going to;

1. disconnect the fans and see how high the internal temp actually gets while floating the batteries.. Interesting to note, during float, only 1 fan is used.. So my thoughts are if just 1 fan can be disconnected (bridged with resistor to not get FAN lock errors).

2. Reverse the fans to check temp differences. 

3. Sell and upgrade to Victron.

Link to comment
Share on other sites

13 hours ago, JamesF said:

If anyone has experience with the .hex firmware, please let me know?

That would be me, or my colleague Weber. I do most of the "blue sky" low level research that enables the higher level code (e.g. AussieView™) that he largely wrote.

Unfortunately, many of the 24 V models use a Freescale HCS08 microprocessor, which is quite unpleasant to deal with. The "hex" files for those are actually Motorola S19 files.

Since these models are not of major interest to me, I've not even found the fan control logic, or even which GPIO lines control the fan(s).

If it happens to use a TI DSP chip, then things are a bit better, and I can likely guide you to the fan control function, provide you with a disassembly of that function, and general patching guidance if you need/want it.

But step zero is finding a hex/s19 file to work from. You can't realistically extract it from flash memory.

Link to comment
Share on other sites

On 2021/08/03 at 10:32 AM, Coulomb said:

That would be me, or my colleague Weber. I do most of the "blue sky" low level research that enables the higher level code (e.g. AussieView™) that he largely wrote.

Unfortunately, many of the 24 V models use a Freescale HCS08 microprocessor, which is quite unpleasant to deal with. The "hex" files for those are actually Motorola S19 files.

Since these models are not of major interest to me, I've not even found the fan control logic, or even which GPIO lines control the fan(s).

If it happens to use a TI DSP chip, then things are a bit better, and I can likely guide you to the fan control function, provide you with a disassembly of that function, and general patching guidance if you need/want it.

But step zero is finding a hex/s19 file to work from. You can't realistically extract it from flash memory.

Thanks. I am meeting with a supplier of my particular unit tomorrow, and I will attempt to get the firmware. I have also requested it from the Vendor!

Link to comment
Share on other sites

More investigation on this topic:

When the device is in battery mode - ie, no input at all from PV or utility and running on batteries, the fans switch off during low loads. (my tests were under 15%) Keeping the load constant, I found that the internal temperature of the unit did not surpass 42deg C. The fans did not come on at all.

I dropped the load to minimum - 0% - 1Ah - and found the internal temperature drops further to 37deg c where is sits happily. I left the unit like this for about 24 hours, and the fan did not come on at all.

So far, the fans are only constant during the charge and float of the batteries, and internal temperature above 40deg C.. (both PV and utility) 

Link to comment
Share on other sites

14 hours ago, JamesF said:

When the device is in battery mode - ie, no input at all from PV or utility and running on batteries, the fans switch off during low loads.

Well, that's different to the latest 5 kVA firmware for MKS IIs that I have (71.86). It has a minimum of 30% speed all the time. Same as my MKS non-IIs. But I note that at 30% speed, they are very quiet, and you might need a torch to see if the blades are actually spinning, unless it's very quiet where the inverter is.

But the 24 V models might well be different.

Link to comment
Share on other sites

This is my solution for the noisy fans of the MKS-II, it isn't cheap, but extremely good, there is basically zero noise anymore. The only issue when upgrading to those silent fans is the screwy pinout of the fan connectors of the MKS-II, some pins have to be swapped, but no bigger deal, the NF-A8s comes with some extension cables which can be misused for that purpose, so the connectors of the fans themselves can remain as they are. Mine are perfectly running since about 3 years by now, and I'm just upgrading to an Axpert VM-III, and the same issue there, so the fans will now move to that inverter.

20210809_163859_4MP.thumb.jpg.3b8355527e3b18d58830824b86be3358.jpg20210809_163649_4MP.thumb.jpg.8da605524ee6c2f9a6c2071eee522b0f.jpg

Link to comment
Share on other sites

12 hours ago, Wolfgang Griech said:

This is my solution for the noisy fans of the MKS-II, it isn't cheap, but extremely good, there is basically zero noise anymore. The only issue when upgrading to those silent fans is the screwy pinout of the fan connectors of the MKS-II, some pins have to be swapped, but no bigger deal, the NF-A8s comes with some extension cables which can be misused for that purpose, so the connectors of the fans themselves can remain as they are. Mine are perfectly running since about 3 years by now, and I'm just upgrading to an Axpert VM-III, and the same issue there, so the fans will now move to that inverter.

20210809_163859_4MP.thumb.jpg.3b8355527e3b18d58830824b86be3358.jpg20210809_163649_4MP.thumb.jpg.8da605524ee6c2f9a6c2071eee522b0f.jpg

What did you pay for those fans and where did you buy them from may I ask?

Link to comment
Share on other sites

2 hours ago, sunset1 said:

What did you pay for those fans and where did you buy them from may I ask?

sure, no secrets about any of this, am happy to share it, but I'll have to tell you I'm living in the Philippines, so no clue where you could buy them from. My source was Lazada, an Asian small version of Amazon, here's a link for buying at Lazada, and you wanna chose the 12V 4PIN PWM version of it:

https://www.lazada.com.ph/products/noctua-nf-a8-80mm-computer-cooling-fan-12v5v-3pin4pin-pwm-quiet-radiator-fan-for-pc-case-cooling-cpu-cooler-replace-fan-i1750436467-s7493248143.html?

the cost is right now quite exactly $30 USD / piece, so quite expensive, but IMHO well worth the money, in our case the inverter is outside in an open shed just a couple of meters away from our bedroom, so quite annoying at night when everything is silent and you'll sleep with the windows opened. And those fans are really silent, and also no ball bearings or alike, I think it's magnet bearings, with an MTBF of 100,000h or alike, so very likely you'll never have to exchange them again.

today I'll take them out from the old inverter and transfer them into the new Axpert VM-III 5kVA, I'll take some pics of the wiring and share it here later.

 

 

Link to comment
Share on other sites

I have the same fans here since more than a year, but didn´t install them so far.

I´m running a MPP Solar PIP 5048GK that should be identical to the Axpert VM-III - MPP Solar provided a firmware update that reduced the fan noise under lower charge, but cannot provide a solucion when the fans are running with full speed.

@Wolfgang, did you invert the fan blowing direction?

Link to comment
Share on other sites

On 2021/08/11 at 1:52 AM, Peter Merle said:

I have the same fans here since more than a year, but didn´t install them so far.

I´m running a MPP Solar PIP 5048GK that should be identical to the Axpert VM-III - MPP Solar provided a firmware update that reduced the fan noise under lower charge, but cannot provide a solucion when the fans are running with full speed.

@Wolfgang, did you invert the fan blowing direction?

@Peter: yes I did on the original MK-II, but found out that the inside of that inverter is really dusty and even dirty, so at the VM-III now (yes, I did this the day before yesterday) I kept the original direction, blowing out to the bottom. I know this is against all good design rules and against the natural flow of the heat, but the dirt and the fact that there are non-removable non-cleanable filters on the inside of the inverter made me think a bit, so guess for now I'll stay with the original direction. This time I also decided to cut off the original fan connectors with about 5cm, and solder them to the Noctua NF-A8 fans, after I discovered that those geniuses used one connector with 3 pins and the other one with 4 pins:

20210810_152910_4MP.thumb.jpg.53152bf709727784aa86ca28ede12728.jpg

this is the soldering connection between Noctua (left) and the original fan connector (right), yellow-right is connected to RPM = green-left, PWM is not used at the VM-III, they probably just control the fan voltage:

20210810_173329_4MP.png.bab5ecec21c611d16b9ff6cb2961aa5f.png

the whole installation of the 2 Noctua NF-A8 fans looks like below, it is quite tough to pull the brown plastic holders of the Noctua due to tight space: 

 

20210810_152807_4MP.thumb.jpg.9b0f13f920c19fcf2760483999a73e59.jpg

and finally a pic of the non-removable non-cleanable filters, the only good idea I would have to clean them is to use a vacuum cleaner from the outside, and this only works if we maintain the original direction of the fans, else those filters will get plugged from the inside:

20210810_154122_4MP.thumb.jpg.feebb76df1c15fe5501dd867741298b6.jpg

Link to comment
Share on other sites

On 2021/08/11 at 1:52 AM, Peter Merle said:

I have the same fans here since more than a year, but didn´t install them so far.

I´m running a MPP Solar PIP 5048GK that should be identical to the Axpert VM-III - MPP Solar provided a firmware update that reduced the fan noise under lower charge, but cannot provide a solucion when the fans are running with full speed.

@Wolfgang, did you invert the fan blowing direction?

@Peter: yes I did on the original MK-II, but found out that the inside of that inverter is really dusty and even dirty, so at the VM-III now (yes, I did this the day before yesterday) I kept the original direction, blowing out to the bottom. I know this is against all good design rules and against the natural flow of the heat, but the dirt and the fact that there are non-removable non-cleanable filters on the inside of the inverter made me think a bit, so guess for now I'll stay with the original direction. This time I also decided to cut off the original fan connectors with about 5cm, and solder them to the Noctua NF-A8 fans, after I discovered that those geniuses used one connector with 3 pins and the other one with 4 pins:

20210810_152910_4MP.thumb.jpg.53152bf709727784aa86ca28ede12728.jpg

this is the soldering connection between Noctua (left) and the original fan connector (right), yellow-right is connected to RPM = green-left, PWM is not used at the VM-III, they probably just control the fan voltage:

20210810_173329_4MP.png.bab5ecec21c611d16b9ff6cb2961aa5f.png

the whole installation of the 2 Noctua NF-A8 fans looks like below, it is quite tough to pull the brown plastic holders of the Noctua due to tight space: 

 

20210810_152807_4MP.thumb.jpg.9b0f13f920c19fcf2760483999a73e59.jpg

and finally a pic of the non-removable non-cleanable filters, the only good idea I would have to clean them is to use a vacuum cleaner from the outside, and this only works if we maintain the original direction of the fans, else those filters will get plugged from the inside:

20210810_154122_4MP.thumb.jpg.feebb76df1c15fe5501dd867741298b6.jpg

Link to comment
Share on other sites

here a few pics of my original MK-II installation with those Noctua NF-A8 silent fans:

20210810_091734_4MP.thumb.jpg.af2e8acc5572e9133c34adb04f570310.jpg

20210810_092108_4MP.thumb.png.45719b58e5195e39a08907624ce0529c.png

as you can see I have swapped the yellow and green wires of the Noctua extension cable before directly gluing them onto the PCB, after pulling the original white connector bodies from it. There was no other reasonable way without cutting the Noctua cables, which I have done now anyway for the VM-III 😉

20210810_092201_4MP.thumb.jpg.7dae4a4073af2e86d549bc67155dadf3.jpg

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share

×
×
  • Create New...