Flexcharge NC25A Charge Controller 25A – 24V

$158.00 $96.00

SKU: NC25A/24 Category:

Volume discount pricing

Inventory sale valid in the continental US only.

The Flexcharge NC25A is a high efficiency charge controller for solar and wind energy systems with a maximum charging rate of 25 Amps. It works with lead acid GEL, AGM, and flooded cell deep-cycle batteries; it also works with wet cell NiCad batteries.

The NC25A is a series controller designed for alternative energy charging systems ranging in size from 0.1A to 25A.  It is the ideal regulator for Solar (PV) and Permanent Magnet Generators (Including outboard motors and smaller wind generators). The NC25A also includes a Charge Divert feature.  Charge Divert allows you to use the excess charging source energy for other tasks, or for placing a load on permanent magnet charging sources such as wind generators to prevent over speed conditions.

The Divert connection is only activated after the charging source is making energy and the batteries are not using the energy (i.e. A wind generator will not be starting into the divert load). This charge controller can easily and inexpensively be expanded to handle one or more banks of 100A charging sources. Multiple battery banks can be charged with the use of a standard battery charging isolators. Please see page 21 in the manual.

The NC25A includes easy to read Charge and Divert Indicators, an adjustment for peak charge voltage, and an easy to use terminal strip for the system wire connections.  Because the system charge controller is usually located near the battery bank in a remote structure we chose not to incorporate power consuming monitors such as volt meters or current monitors. If this type monitoring equipment is desired it should be installed after the system disconnect switch and located where you can view them.

Features off the Flexcharge NC25A charge controller:
– 5 year warranty.
– Completely sealed electronics for marine or outdoor mounting.
– Low Battery Voltage indicator (flashing red light).
– Arc reduction circuitry to eliminate or reduce relay contact wear.
– Charging efficiency better than 99.50% from 0.5a to 30a of charging current.
– Operates efficiently (98%) with as little as 0.1a of solar panel charging current.
– Efficiently charges batteries from 0 volts with full power.
– 25 amp charge capacity.
– 25 amp charge divert circuit.
– Diverts only when voltage and current are at usable levels. perfect for motor type divert loads (fans, pumps, etc…)
– Peak charge voltage adjustment with a range of 13.8v to 15.9v (multiply by 2,3,or 4 to find voltages for 24v, 36v, or 48v versions).
– Charges with the same high accuracy through battery isolators.
– Consumes less than 5ma (0.005a) while charging and at night (2ma if you do not use the charge indicator).
– Charges batteries at full power, below the plate saturation point, this charges batteries faster, and reduces electrolyte depletion by up to 90% over conventional constant voltage, pwm, & high frequency charge regulators.
– Batteries start charging at 0.005a of charge current.
– Controller can withstand open circuit input spikes of 1500v/a, & 140v continuous without damage.
– Reverse polarity and transient voltage protection on the battery sense wires.
– Remote battery voltage sensing so the controller can be mounted anywhere between the charging source and the batteries.
– Easy to install using the labeled corrosion resistant nickel / brass / stainless steel connector.

NC25A-24 Operating Characteristics
Flexcharge NC25A-24
Charge Input Voltage: 0Vdc – 140Vdc
Allowable Battery Voltage on Sense Wires: 0Vdc – 32Vdc
Standby/Operating Current of the Controller: 2mA – 7mA
Charging Amperes: 0.005A  – 25A
Total Charging Efficiency: 98.9% – 99.8%
Case Dimensions: 4″W x 3.75″H x 1.5″ D



Flexcharge is the trademarked name for all products manufactured by Seelye Equipment Specialists (SES). SES was established in 1967 and currently have offices in Charlevoix, Michigan. The success of the Flexcharge product line and exceptionally low level of warranty returns is a testament to the level which they have achieved their goals. Flexcharge products are designed with the "install and forget" philosophy. Their charge controllers are operating in harsh environments around the world such as Antarctica, Alaska, Africa, Saudi Arabia, Florida and Canada, Mount Everest and more.

Flexcharge NC25A


User and installation manual for Flexcharge NC25A Charge Controller 25A – 12V