Hey Folks,
I am planning to power my hi-sites with Solar Power. Will my solution shown below work?
EDIT: Also refer to the new Wiki Article addressing this topic for more info: http://wiki.mikrotik.com/wiki/Solar_Power_HOWTO
you will need at least twice the panel power - better would be 24V 120W
Thanks for the reply.
Please can you explain why this is necessary?
I used two or three different websites to calculate this and they all seemed to agree.
Perhaps I should point out that I am located on the equator in kenya.
Regards,
Alex
you only can use about 80% of the daylight - as long as your panels are fixed
the pax power of a solar panel is alwas given with 25°C panel temteratur - when they get hotter the
output goes down
only about 65 to 70% of the energy is loaded int the battery …
I would use larger panels too. Things change quickly with the Internet and you’ll want to add more radio cards or a different routerboard at some point in the future without having to redesign the whole system. If the cable run isn’t too long, I’d prefer a 12v system.
HEy Folks,
Thanks for the tips.
I have now bought the follwoing:
1 x 100Watt 24 Volt Panel
1 x 15Amp 24Volt Charge / Load Controller with Low Voltage Disconnect
2 x 44Ah Low Maintenance Deep Cycle Batteries
Funnily enough two 40 watt 12 Volt panels cost the same as 1 100 Watt 24 Volt Panel. About 400 US Dollars for the Panel.
@ JP why would you prefer the 12 Volt system? I figured that the RB are all quite wide ranging in voltage but the RB 433 Manual actually states that 24Volt is the best choice and that they have tested it with charging voltages ap at around 29Volts…
This has been quite a learning experience, as there are so many variables that accounting for them all properly is a mission!
Cheers!
Alex
p.s. Will send photos of the rig when its built.
Well, every need is a little different, but I needed to be able to run a 12v inverter. 24v under charging conditions can exceed 24v by a fair amount and I did not want to put too much voltage into the RB. My rb is only 2’ from the batteries, if you have a long poe cable run, it would likely be a lower voltage. At other sites, the equipment either uses 12v or converts from 12v to what is needed. 24v would be preferable anywhere there are long cable runs, either for the solar panels or for the load. Probably not an issue in Kenya, but here we also grease all the battery connections to prevent corrosion as well.
Hi There,
Well, its been an interesting few days learning about this. to this end I have started writing a wiki article to try and document my lessons for others. http://wiki.mikrotik.com/wiki/Solar_Power_HOWTO
Thank you for clarifying the 12v point. I see what you are getting at.
I decided not to use the POE, and will instead run a dedicated copper cable up the mast (35 Meters) to the regular Power Socket on the Routerboard, for voltage drop reasons.
I am now testing it. Wish me luck.
Alex
I have a couple 24 volt solar sites using Morningstar charge controllers. This summer I replaced some older Routerboards at one of the sites with RB4xx’s and everything has been fine until a few weeks ago. As the temperature has been dropping, I’ve been having problems with the RB4xx’s going offline during the day. By the time I would drive out to the tower they would be running again.
After a couple days of this happening, I found out that the Morningstar PS-30 I’m using has a temperature sensor that increases the charge/boost/float voltages for the lower temperatures. Instead of having the normal 28.8 volt charge voltage, it was putting out over 30 volts which was causing the Mikrotik to go into over voltage protection..
I wired a resister on my load side to drop the output voltage into an acceptable range for the Mikrotik and everything has been find since.
Just something to keep in mind depending on the controller your using.
-Gerard
Great update gerard. A great tip.
It is similar to the first problem I have seen on my new test rig. Only in reverse.
My test rig is running the newer boards, Crossroads and RB433 (which I designed it for), but my older RB532 wont power at all. This is because when the voltage drops below 25V the RB532 with the jumpers set for high voltage (25-48V) means it doesnt get enough juice.
Then the Low Voltage setting is like 12-24 or something cant quite remember. When the voltage of the battery bank comes down below 25V the RB532 quits…
I am thinking of putting a DC-DC converter to step this down to a 12V for the RB532. Dont wanna do it though. Too many conversions just causes losses.
Well, the lessons you learn.
Cheers!
Alex
I have created a wiki article to document the process of making a solar power system. Hopefully this will help others.
The article is found here: http://wiki.mikrotik.com/wiki/Solar_Power_HOWTO
How much can cost the solar panel like that?
This is a bit late but I like to get my 2cents in. I have 7 solar powered sites in production, the oldest is about 4 years. They all run 12v as the panel, battery and radio’s are mounted together at the top of the tower for security reasons. 12v has so far served me well, not having any of the problems described above. I’ve changed from RB532 to RB433’s on several sites without hassle.
The solar wiki rocks. good job.
I’m gonna run RB433 and RB600 on 12V over networklinks of 10km’s. Put injectors in the panel box and in the battery box to run the system over POE. The test I did were ok. Load is fine. I use 75W solar panels and 120Ah 12V Batteries.
I run since 2005 a network over 15km in the same set up but then with WRAP PC’s. I changed one battery in October 2008. Just let me know if you need a network diagram.
The photos of the batteries in the wiki article appear to be a 12v setup (parallel 12v batteries). Otherwise, a good wiki article.
Hey jp…
Busted… you caught me out. The photos ARE actually of a 12v system. Its a different site than originally used in the article…
BTW for others I started using a really cheap Chinese charge controller, and it was fine, but an accidental shorting of the load side caused me to go and buy another one.
I bought one made by Steca and I have to say its WAY better. More expensive at 100 USD but the built in monitoring features etc are great, and the charging is more thorough for VRLA batteries…
Steca is de way to go. 100USD? In South Africa it’s +/-35USD for Solsum (10A). Check http://www.stecasolar.com
The one I got for 100 USD is the Steca PR1010 which is a 12/24 volt 10 amp unit with lcd screen and bunch of monitoring functions. I dont know the model you suggest.
But then everything in Kenya is a rip off these days… ho. hum.