Hood Solar Panel

[geomars]

For those of you who have installed solar on your LC, how do you address the instructions on page 550 of the manual to (a) never recharge when the hybrid system is on, and (b) have all accessories turned off. Do you only turn on the solar when the hybrid and accessories are off? Do you have a battery charge-current limiter or relays that only connect the solar charge controller to the battery when the hybrid and accessories are off? Do you ignore the warning?

One consideration is the warning on page 549 in the manual that the battery might explode if it is charged at a rate >5 amps. If the hybrid system is charging the battery at the approved rate, and then a solar panel provides an additional 5 amps (achievable with only ~60 watts), the charge will be 10 amps, double the specified max.

 

[EOD Guy]

My roof mounted solar charger is connected directly to the 12v battery, it runs 24/7 and I haven't had an issue since I installed it.

 

[geomars]

My roof mounted solar charger is connected directly to the 12v battery, it runs 24/7 and I haven't had an issue since I installed it.

What solar charger are you using? Maybe it detects the charge from the LC charging system (14.4v) and reduces the charge from your solar panel, as if the battery was fully charged. Then when you turn off the LC and the solar charge controller detects only the battery voltage, the solar kicks in.

 

[EOD Guy]

What solar charger are you using? Maybe it detects the charge from the LC charging system (14.4v) and reduces the charge from your solar panel, as if the battery was fully charged. Then when you turn off the LC and the solar charge controller detects only the battery voltage, the solar kicks in.

I never thought of it like that, but you logic is sound and may be what's happening (IDK) I was a little apprehensive for the 1st month after installing the solar charger, checking my digital voltage meter (I also installed for a different reason) probably 2-300 times for over charging, but it never showed over 12.9 volts. This is the one I used, I cut off the clips and direct wired it to a 60amp circuit breaker and the C/B wired to the unused 200 amp fusible link (under the red, pos post battery cover) I've not had any issues.

 

[geomars]

I never thought of it like that, but you logic is sound and may be what's happening (IDK) I was a little apprehensive for the 1st month after installing the solar charger, checking my digital voltage meter (I also installed for a different reason) probably 2-300 times for over charging, but it never showed over 12.9 volts. This is the one I used, I cut off the clips and direct wired it to a 60amp circuit breaker and the C/B wired to the unused 200 amp fusible link (under the red, pos post battery cover) I've not had any issues.View attachment 48148

View attachment 48147

There’s another factor in your favor for not charging at too high a rate: the power of your panel is 20 watts—corresponding to 1.4v to 1.7amps—good for maintaining a charge, but even if it were added in parallel to the LC charging system, would only cause a modest excess to the specified maximum current. A more serious violation of guidance in the owner’s manual could arise with a solar panel of 100w (7 to 8 amps at full power).

 

[EOD Guy]

There’s another factor in your favor for not charging at too high a rate: the power of your panel is 20 watts—corresponding to 1.4v to 1.7amps—good for maintaining a charge, but even if it were added in parallel to the LC charging system, would only cause a modest excess to the specified maximum current. A more serious violation of guidance in the owner’s manual could arise with a solar panel of 100w (7 to 8 amps at full power).

Hince solar charger vs solar panel

 

[GaryA]

So are you'll saying that the 115w charger from Lensunsolar.com is not good for our LC . I'm confused. The panel would do two things, keep the glare down and charge the battery for my dash cam.

 

[sweet5ltr]

So are you'll saying that the 115w charger from Lensunsolar.com is not good for our LC . I'm confused. The panel would do two things, keep the glare down and charge the battery for my dash cam.

I don't think lensunsolar cares if your LC250's 12V battery explodes.

Low probability - but they didn't place the warning in the manual for no reason.

 

[geomars]

So are you'll saying that the 115w charger from Lensunsolar.com is not good for our LC . I'm confused. The panel would do two things, keep the glare down and charge the battery for my dash cam.

I would be concerned if the charge controller that is used with the panel puts more than 5 amps into the battery on its own, or puts power into the battery when the LC is charging the battery, bot of which are warned against in the manual.

On the other hand, the advantage of having a 115w panel is for when the sun angle is low or the sky is cloudy, and the panel is putting out less than full power. In that situation you would be more likely to get the Land Cruiser’s allowable 5 amps at 13 or 14v (65-70w). A panel rated at 65-70w wouldn’t exceed the allowable 5 amps (except perhaps by a small amount in cold weather when the panel might exceed its rated power), but at an oblique sun angle or with cloud cover the smaller panel wouldn’t put out the full 5 amps. So there is a benefit to the larger panel if you can limit it’s power when the sky conditions are favorable for power.

If it was on my LC, I’d check if the charge controller lets you specify maximum charging current (or battery size if the controller uses this to calculate max charging current). Alternatively, I’d look into using a current-limiting circuit. Either approach would have the advantage of being able to use your 115w panel without the panel putting more than a specified amount (5amps) into the battery.

But limiting current alone doesn’t resolve the issue of the solar panel charging while the LC is charging. A simple switch would do that, though. Or, alternatively, a more elegant option would be a relay that disconnects the panel when the hybrid system turns on.