MorningStar SunKeeper 12 Amp 12 Volt PWM Charge Controller
Manufacturer Part Number: SK-12
Morningstar’s SunKeeper (SK-12) solar controller provides a low cost regulated output directly from the solar module to maximize battery life in small solar power applications. The SunKeeper is epoxy encapsulated and rated for outdoor use. By mounting directly to the module junction box and wiring through the junction box knockout, the connection is weather-proof. This eliminates the need for an additional housing for the controller.
The SunKeeper is available in a 6 amp or 12 amp version (both at 12 volts DC). To withstand the high temperatures at the solar module, the controller has been designed using extremely efficient power electronics and is rated to 70°C. The SunKeeper is also certified for use in Class 1, Division 2 hazardous locations, making it an ideal controller for solar powered oil/gas applications.
A typical SunKeeper System.
Rated to 70°C to operate in high temperatures at the solar module.
More reliable than controllers mounted inside the junction box. Uses
very low on-resistance power MOSFET’s. No need to re-rate.
ETL approved for outdoor use without an additional enclosure. Rugged
IP65, UV resistant case. Epoxy encapsulated printed circuit board and
watertight connection to the module junction box.
Extensive Electronic Protections
Fully protected against reverse polarity, short circuit, overcurrent, lightning
and transient surges, high temperature and reverse current at night.
|Rated Solar Input:|| 6 amps||12 amps|
|Nominal System Voltage|| 12 Volts|
|Min. Battery Voltage|| 0 Volts|
|Max. Solar Voltage|| 30 Volts|
|Self-Consumption|| Charging: 7 mA|
Night: 2 mA
|Voltage Accuracy|| +/- 150 mV|
|Regulation Voltage|| 14.1 Volts (at 25°C)|
|Float Voltage|| 13.7 Volts (at 25°C)|
|Type of Charging|| Series PWM|
3 stage: bulk, PWM and float
|Temperature Compensation (3 choices)
||Reading temp at controller: –30 mV / °C|
Attaching remote temp sensor: –30 mV / °C
Disable temp comp: Defaults to 25°C
- Reverse Polarity
- Short Circuit
- Lightning and Transient Surges
- High Temperature
- Reverse Current at Night
- Operating Temperatures: – 40°C to +70°C
- Humidity: 100%
|Tropicalization:|| Encapsulated in epoxy|
|UV resistant plastic enclosure|
|Conduit connection with rubber gasket seal|
|Dimensions:|| 99 x 51 x 13 mm|
|(3.9 x 2.0 x 0.5 inches)|
- Weight: 0.11 kg / 0.25 lbs
- Enclosure: IP65
- Fitting to Module J-box: PG 13.5, M20, 1/2 inch conduit
- Wire Size: 2.0 mm2 (#14 AWG)
- Wire Terminations: #8 fork connectors
|Green Blink|| 3 Times Successful installation|
|Green On|| Solar charging battery|
|Green Blink Fast|| In regulation|
|Green Blink Slow|| Normal nighttime operation|
|Red On|| Controller damaged|
|Red Blink|| System problem|
|LED Off|| No power|
- Remote Temperature Sensor (RTS)
- CE Compliant
|Hazardous Locations:|| Class 1, Division 2, Groups A-D,|
|CSA 22.2 No. 213-M1987|
- Complies with U.S. National Electric Code
- Manufactured in a Certified ISO 9001 Facility
Longer Battery Life
Series PWM with 3 stage charging: bulk, PWM regulation and float.
Includes temperature compensation at the controller or alternatively at
the battery when using optional remote temperature sensor. Able to
charge a zero voltage battery.
The SunKeeper battery charging algorithm is optimized
for sealed lead-acid batteries. There are four main
stages to the charging algorithm:
- Night – There is no solar power available, the
solar module is disconnected from the battery to
prevent nighttime reverse current leakage.
- Bulk Charge – Solar power is available, the
battery is recharging and has not yet reached full
- Regulation – The battery has charged to the
Regulation setpoint, the SunKeeper is limiting solar charging current to prevent battery overcharge while bringing the battery to full state-of–charge.
- Float – The battery has reached full state-ofcharge
and the SunKeeper has reduced battery
voltage to the lower Float setpoint.
- Temperature Compensation - Lead-acid battery
chemistry changes with temperature. The
SunKeeper adjusts the Regulation and Float
voltage setpoints as temperature changes so that
the battery is correctly charged. The user may
choose to add an RTS (purchased separately), or
use the internal temperature sensor. Temperature
compensation can also be disabled.
- Maximum Charge Voltage – The SunKeeper
limits the charge voltage to 15V, regardless of
ambient temperature, so that voltage-sensitive DC
loads are not damaged.
- Night Disconnect – The SunKeeper periodically
checks for nighttime condition. When night is
detected, the SunKeeper disconnects the solar
module to prevent reverse current leakage. An
external blocking diode is not required.
Rated for Hazardous Locations
Specifically designed for solar power systems in the oil/gas industry.
Approved for use in Class 1, Division 2, Groups A,B,C,D.
Bi-color LED is easy to read from the ground when the solar module
is pole-mounted. Indicates solar charging, regulation, normal nighttime
operation and any controller or system faults.
Easy to Install
Fits standard half inch conduit knockout (PG 13.5, M20) in module
junction box. Quickly fastens with included locknut. Wires have fork
connectors for easy connection to solar module terminals.
The SunKeeper is fully protected against system faults
listed below. Recovery is automatic except where
noted below. Refer to section 3.0 for fault LED
- Reverse Polarity Solar (LED OFF) – no charging,
disconnects solar module until wired with correct
- Reverse Polarity Battery (red blinking LED) – no
charging, displays fault until battery wired with correct
- Short Circuit Solar (LED OFF) – stops charging until
short clears or will enter Night stage (LED OFF) if fault
- Charging Over-current (red blinking LED) –
charging current has exceeded SunKeeper current
rating; fully automatic recovery; retry every 10
- High Temperature Condition (red blinking LED) –
ambient temperature is too high; charging
automatically resumes when SunKeeper has cooled to
a safe temperature.
- Temperature Sensor Failure (red blinking LED) –
detects a failure in the SunKeeper’s internal
temperature sensor or a disconnect of the Remote
Temperature Sensor (if used). Fault persists until the
problem is corrected.
- System Wiring: Use copper wire only. Power
conductors should be joined or spliced using insulated
butt splice solderless crimp connectors or by brazing,
welding, or soldering wire ends. If soldered, the
spliced joint should be mechanically and electrically
secure before soldering. All splices and joints should
be covered with insulation equivalent to that of the
- System Fusing: The battery positive lead should be
fused no further than 12 inches (305 mm) from the
|SK-6|| 8A fuse|
|SK-12 || 16A fuse|
- Temperature Compensation Select: The SunKeeper
has three temperature compensation options. The blue
Temperature Compensation Loop can be configured
for the following temperature compensation options:
- Loop not cut: Internal temperature sensor used for temperature compensation (factory
- Loop cut, left open: No temperature
compensation. Insulate/cap loose ends.
- Loop cut, connected to RTS: Remote
Temperature Sensor (RTS) used for
- Plastic mounting feet are included with the
SunKeeper to allow for surface mounting.
Warranty: Five year warranty period. Contact Morningstar for complete terms.