Tristar 45 PWM Custom Profile

[kp_utah]

First..... I have a few images in this to help illustrate. Views best if you are allowing images! I tried to repeat in text what the image was saying, but a picture, as we know, is worth more.



I have two 100W solar panels, leading into a Tristar 45 PWM.
I have two Trojan T-105 batteries in series to make a 12V system.

I see that the default settings for the DIP switches don't exactly get you to what Trojan recommends for their batteries.

OK I read up that in order to customize the profile, you need a usb-to-R232 cable connected to a computer running MSView. Cool. I recently went thru 2 USB-to-R232 cables bought via eBay before buying the named brand. Lesson there!! The cheap ones from across the pond didn't work. After some research on the r232 cables. The fakes can't read the firmware drivers, etc and if you go into Device Manager you will see an error on your device. This is also noted from Morningstar that many have this issue. I just bought the recommended brand (Tripp-Lite U209-000-R) and it works great!! Cool. Onward now to getting my Tristar setup for the Spring usage (still snow on ground here in Utah).

So, I have started to try to understand how to use MSView to get the exact specs that Trojan asks for on their batteries.

Trojan specs say:

• 14.82 - Bulk Charge
  
• 14.1-14.7 Absorption Charge
  
• 16.2 - Finish Charge
  
• 16.2 - Equalize Charge
  
• 13.5 - Float charge
  

(the following is an attempt to add in the picture of voltages...)


And the map from the specs translates to this:


The charging temperature compensation says: Add .005V for every 1C below 25C and substract the same for below 25C. (.0028V for every 1F below 75F). I prefer Farenheit, but it looks like the Tristar prefers Celius. So, I will work with that.

(the following is an attempt to add in a picture of the temperature compensation...)



Charge Mode - PWM, Temp Comp & Reminder
On Screen 1 for the Setup wizard, I currently have set:

• PWM Voltage (Absorption) 14.2 V@25degC
  
• Battery Temperature Compensation .005 V/degC
  
• Maximum Compensation Temp 80 degC
  
• Minimum Compensation Temp -40 degC
  

(checkbox) Enable Battery Service Reminder

• Battery Service Reminder 30 Days

If the following pic comes thru, I highlighted the values I changed. I put absorption to 14.2, battery temp comp to .005 (but it changes to .004). IDK why. And service reminder to 30 days.



Question 1: I tried to set temp comp to .005 per Trojan requirements, as soon as I go past that screen, and come back, MSView pushes it back to .004. I assume that is negligible. Agreed?

Question 2: I am not sure what to set max/min temp too? It defaulted to 80C max, -40C Min. I assume that is just fine, both are very extremes, and its just saying to me, that it will compensate 100% of the time. Any issues there? After all, if we get to 80C (176F) or -40C (-40F) we all have a lot of other problems.

Question 3: It defaulted Battery Service Reminder to 60 days. I changed mine to 30 days. Trojan says to check it often. I am not sure "where" its going to remind me though. LOL. Is 30 too often? I assume this is really just a personal preference.



Charge Mode - Float Settings
Ok, onto the next dialog/screen

This one is about Float charges. So, I see that Trojan recommends Float Voltage to be 13.50. No Problem, I set that (it was defaulted to 13.7). On this screen, the rest of the settings are not as clear to me. Suggestions?

All settings are:

• Float Voltage 13.5 v@25degC
  
• Transition to Float when duty cycle is 30% or less for 0h 0m 0s
  
• Exit Float when duty cycle is 100% for 1h 0m 0s
  
  
• Y/N Enable Low battery trip
  
• Low Batt trip voltage 12.50V
  
• Low Batt trip timer 0h 0m 0s
  
  
• Y/N Enable Float cancel
  
• Float cancel voltage 12.38 V

Question 4: Do I need to worry about any other settings on this page? I am very curious what everyone else is setting on these? The best strategy?

Question 5: I believe the float cancel voltage should be set to something that coordinates with the state of charge percentages for the battery. For this battery, it says

• 100% - 12.74v
  
• 90% - 12.62v
  
• 80% - 12.5v
  
• 70% - 12.38v
  
• 60% - 12.24v
  

So, what percentage or voltage should Float cancel kick in? 70% or 80%? I have currently set it to 12.38 or 70%. Good or bad?




Charge Mode - Equalize & HVD Settings

Question 6: Given that Trojan recommends 16.2V for equalization, what would be the suggested settings for the rest of this screen? I honestly guessed at these.

• Equalize Voltage 16.2V@25degC
  
• Equalize Time 1h 0m 0s
  
• Auto Equalize interval 28 days
  
• Equalize Timeout 3h 0m 0s
  
  
• High Voltage Disconnect 16.30v
  
• High Voltage Reconnect 14.00v

LED Settings

Really no question here other then curiousty. I set mine to align with the percentages.100, 90, 80, 70. What are others doing?

• 100% - 12.74v ----Green Only
  
• 90% - 12.62v ----Green and Yellow
  
• 80% - 12.5v ----Yellow Only
  
• 70% - 12.38v ----Yellow and Red
  
• 60% - 12.24v
  

I know this is a lot of info and questions. Huge thanks in advance.
(It took me a while to put in those images, and formatting here. As an IT person for my day time job, one suggestion to the forum owners is to look into some more friendly text editor widget. There are some opensource free ones out there that are really cool.)

Thank you!!

[time2roll]

time2roll wrote:
Low battery trip I believe is to restart bulk charge if battery voltage drops for some time during the day due to high loads. If you run the Microwave off inverter for 2 minutes this might trigger bulk stage. I would set the voltage a bit lower like 12.2 on this setting and give about 15 minutes for time.

OK I misunderstood this function.

Low Battery Trip Voltage and Float Cancel are similar functions.

These settings control how long to remain in Absorption.

TRANSITION TO FLOAT is to keep the absorption short when the battery is basically fully charged in storage. Will also delay float if the battery is in light usage. The 30% PWM is basically when your amps have tapered to 30% of panel capacity.

LOW BATTERY TRIP VOLTAGE and the timer is to specify a normal absorption time when the day starts at some value less than full charge. If set at 12.4 then if you start at under 12.4 the timer specifies the absorption timer. So you might give 2 hours as the time to hold absorption.

This function seems optional as the transition to float function will extend absorption until the 30% threshold is met.

FLOAT CANCEL is just that. During hard use and you start below this voltage the controller will hold absorption voltage all day. I would set this fairly low as you did around 11.9 volts.

Sorry for any confusion. My MPPT menus are slightly different.
Click the HELP button on each screen for a brief description of the function on each screen.

[Almot]

Kylepettit wrote:

Almot, I totally forgot to multiple the t compensation. Great catch.

Actually, I wasn't sure that it had to be multiplied - sorry for not making it clear enough. See, controller can detect the battery voltage, i.e. it will "know" the number of cells. Hence, leaving it up to user to do the multiplication job would not be very professional when a hardware chip could do this. In my controller it does this. I only set the per-cell value. In yours - I don't know. Time to read the manual, I guess - this time more thoroughly 🙂

It's not that "Tristar prefers Celsius" - it's that the batteries and all the theory was developed by European scientists hundred years ago. That's why a round 0.005 number for Celsius, and cumbersome numbers for Fahrenheit.

Separate settings for Bulk and Absorb looks odd and unnecessarily complicated. I used to think of the Absorb stage as of a "prolongated Bulk", i.e. you set either Bulk or Absorb, call it what you want, and controller will go into Absorb when voltage gets there. And will stay in Abs for as long as it finds necessary, as per its firmware and user settings.

[kp_utah]

perfect - thank you

[westend]

westend: I can raise the absorption. It would hurt the batteries? I thought max was 14.7 was the limit? You think 14.8 will be ok? yes, I have a remote temp sensor.

14.8 V will not hurt your T-105's at all. You do have the bulk stage set at 14.8V.

6V golf cart batteries benefit from higher charge voltage. I have Sam's Club batteries but they are set in MSView at 14.8V in all stages except float.

[kp_utah]

cool hints. thank you

Almot, I totally forgot to multiple the t compensation. Great catch.

time2roll: I will move to manual equalization. that makes sense. I will try float cancel and low bat trip lower as suggested.

westend: I can raise the absorption. It would hurt the batteries? I thought max was 14.7 was the limit? You think 14.8 will be ok? yes, I have a remote temp sensor.

BFL13: the diagram is what trojan or morningstar had in their pdf. I just superimposed the values. i can try what you said.

[Almot]

T comp is normally 0.005V PER CELL. I am not familiar with this controller but you better make sure that T-comp works out to total 0.03V for a total battery bank. Because 2 Trojans have 6 cells. Hence, 0.005*6=0.03V.

Again, I don't know this controller but normally T-comp feature only works with temperature probe connected. Some manufacturers consider this cable optional. So make sure you have it, and it is connected.

[time2roll]

I would skip the automatic equalization as the voltage is a bit high for some RV components.
Keep this as a manual process.

I believe float cancel is the morning voltage. If the battery gets very low overnight this will trigger the controller to extend absorption for the full day. I would keep this pretty low such as 11.5 to 11.9 volts. Mine is set at 11.9 volts.

Low battery trip I believe is to restart bulk charge if battery voltage drops for some time during the day due to high loads. If you run the Microwave off inverter for 2 minutes this might trigger bulk stage. I would set the voltage a bit lower like 12.2 on this setting and give about 15 minutes for time.

[BFL13]

Note that the diagram shows the voltage climbing during bulk and then goes straight across during absorption. This means you get the batts to 14.8 and leave it at 14.8 until you go to float when the batteries are charged right up. (If they ever get that far during daylight--if not, then the voltage will fall off anyway as it gets dark)

Note that there is no place on that diagram for the high "finish" stage. You can ignore that finish stage business and just do 14.8 till they are charged up and then go to float at 13.x.

Every so often, maybe every three months disconnect the batts from the rig so your 12v systems won't get fried, and do an equalize at 16.2v But first the batts have to be full, so on solar that can mean late in the day and not enough daylight left to do the E. So plan ahead for a sunny day and keep the batts as high as possible the day before, and now they will get full early next day and now you can do the E before it gets dark.

[westend]

If you raise your absorption voltage, the batteries will charge faster. Since you have temp compensation, there should be no worries about goosing them with higher voltage. My experience tells me that T-105's like higher charging voltage---14.8 would be a good target.