Question about charge controller

cizzi

I have a Morningstar ProStar 15-M charge controller and would like to know if the "charging" LED ever goes off when my gel battery is fully charged? Or does it always stay lit for a floating charge at 13.7v ? Thanks.

crewzer

Re: Question about charge controller

cizzi,

I don't have a ProStar-15 manual handy. Here's the relevant section from the -30 manual:

4.0 LED INDICATORS
The 4 LEDs in the lower label indicate system status and various faults. These functions are described below.

CHARGING (LED 1 – green)
ON: battery charging during sunlight (always on during sunlight)
OFF: normal during night (off during sunlight indicates solar reverse polarity or overcurrent)

BATTERY STATUS (LEDs 2 – 4)
GREEN: ON indicates battery is near full charge
BLINKING indicates PWM charging (regulation)
YELLOW:ON indicates battery at middle capacity
RED: BLINKING indicates a low charge state and a low voltage load disconnect (LVD) warning
ON indicates the load has been disconnected (LVD)

My take is that green LED 1 should be on during the day when there's sufficient sunlight. The changer will attempt to "trickle" charge the battery in float mode even if the battery is full.

HTH,
Jim / crewzer

cizzi

Re: Question about charge controller

Thanks that makes sense, this is a beautifull charge controller! I love it. Right now its reading 13.0volts from my battery, what voltage would it have to reach to go into trickle mode you think? I have a Penn State 31AH 8GU1 gel battery. Also, when would it go into PWM charging (regulation mode) ? Is that the trickle effect you were talking about? Cause in the manual there's "float" and "pwm regulation" mode.

SolarJohn

Re: Question about charge controller

I've used the ProStar and can confirm that the green LED is on as long as the sun is shining. I believe the manual tells you at what voltage the controller goes into PWM mode.

I've upgraded to a TriStar with a meter recently, and I can now see EXACTLY what is going on inside the controller. It not only indicates PWM mode, but it gives me a % of charge in PWM mode. It shows battery voltage, charge current, battery temperature, and total amp-hours at the same time. I can switch to other display modes for even more information. I love it!

crewzer

Re: Question about charge controller

what voltage would it have to reach to go into trickle mode you think? I have a Penn State 31AH 8GU1 gel battery. Also, when would it go into PWM charging (regulation mode) ? Is that the trickle effect you were talking about? Cause in the manual there's "float" and "pwm regulation" mode.

Cizzi,

Your battery is a VRLA “gel” type. Your charger’s battery type selector switch should be set to position “1”. The target absorption voltage (“PWM regulation”) is 14.0 V (ref 25 C / 77 F). The target float voltage (which I previously called a “trickle” charge) is 13.7 V.

The charger will switch from “bulk” mode to “absorb” (= PWM regulation) mode when the battery voltage reaches 14.0 V (ref 25 C / 77 F). Once the charger has completed its absorption cycle, it will switch to float mode.

You charger includes a temperature compensation feature, but I assume that you’re not using the optional remote battery temperature sensor. The charger will therefore use its built-in sensor and local ambient temperature to adjust the target voltages (cold temp = higher voltage, warm temp = lower voltage).

Here’s a table that will allow you use LEDs 2 (G = green), 3 (Y = yellow), and 4 (R = red) as a sort of voltmeter:

Falling Voltage (battery discharging)
12.1 V G to Y
11.7 V Y to Blink R
11.4 V Blink R to R

Rising Voltage (battery charging)
13.1 V Y to G
12.6 V Blink R to Y
12.6 V R to Y

HTH,
Jim / crewzer