Flexcharge™ NC25A

The NC25A-(X) a is series regulator designed for alternative energy charging systems ranging in size from 0.1A to 25A. It is the ideal regulator for Solar (PV), Permanent Magnet Generators and Alternators (Including outboard motors and smaller wind generators). The NC25A also includes the 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) Divert Resistor. This controller can easily and inexpensively be expanded to handle one or more banks of 100A charging sources. (1000A max charging current in this configuration). Multiple battery banks can be charged with the use of a standard battery charging isolators.

Years prior to the sale of the first NC25A, the SES Flexcharge product development team took a hard look at what a new alternative energy charge controller’s performance level would need to be to give the user the best possible controller for there needs. From that effort came the following design criteria;

Charge Efficiency

Highest Possible Charging Efficiency . The NC25A holds a Patent for its innovative and efficient charging circuitry.Most alternative energy charge controllers operate at an efficiency of 97%. Off hand, this sounds pretty good but lets go through the numbers for a typical charge controller.

*Power Wasted = (Total Charging Current) x (100% – 96%) x (Typical Battery Voltage). P = 25A x 0.04 x 12.6V = 12.6W of wasted energy.
*The NC25A operates at 99.5% typical charging efficiency. (99.9% at its best).P = 25A x 0.005 x 12.6V = 1.57W
*In comparing the numbers we see a 11 watt gain in charging energy that is available for your battery bank withthe NC25A over the Typical Charge controller.
*Question: How much does an 11W solar panel cost? This is precisely why controller efficiency is so critical.

With a peak charging efficiency of 99.9% and an operating current of only 4mA, more of the systems charging energy will get through a NC25A into your batteries than with any other controller on the market. Models are available for charging 12V, 24V, 36V, and 48V systems. Use with Lead Acid, Gel, or Flooded NiCad battery technologies. Not for Lithium.

Dependability

There should never be such a thing as a compromise to dependability when it comes to an alternative energy system charge controller as these systems are often located in hard to reach locations (mountain tops, ocean navigation buoys, polar regions, etc…). We took great care to design the NC25A for long term unattended operation; extensive transient voltage protection; high steady-state voltage protection (it is not affected by continuous charging input voltages up to 100V, the point where the transient voltage protection kicks in); reverse polarity protection on battery connections; fully sealed electronics for 100% humidity operation; etc… The NC25A is designed for Install and Forget operation.

Simple to Operate

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.

Easy Upgrades Expansion Kits

Upgrading the controller to regulate higher currents can be accomplished easily, and is relatively inexpensive see page 21 in the manual at NC25A Manual 2012.pdf See special instructions for converting the NC25A to a high amperage dump load controller NC25A DUMP LOAD CTL.pdf

Energy State Taper Charge Process

This graph describes the charging process used by all Flexcharge controllers. It has many benefits including greatly reduced gassing during charging and it allows for micro-equalization of Lead acid as well as sealed Gel and AGM battery technologies. Click on the link for more details.

Features

• 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 (99%) with as little as 0.1a of solar panel charging current.
• Efficiently charges batteries from 0 volts with full power.
• 25 amp charge capacity. special order 24v, 36v, and 48v models, or expanded models with charging current capacities up to 2000a when expanded.
• 25 amp charge divert circuit. stable divert circuitry prevents erratic relay switching if charge source voltage drops.
• 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.
• No power wasting sample periods.
• Remote battery voltage sensing so the controller can be mounted anywhere between the charging source and the batteries and still be accurate.
• Easy to install using the labeled corrosion resistant nickel / brass / stainless steel connector.
• U/l 94v-o rated enclosure and ul listed or recognized components.

NC25A-12 Operating Characteristics

Flexcharge NC25A-12 (24, 36,48)	MIN	MAX
Charge Input Voltage	0 VDC	140 VDC
Allowable Battery Voltage on Sense Wires 12V Systems (Multiply by 2, 3, or 4 for 24V, 36V, or 48V Systems)	0 VDC	16 VDC
Standby/Operating Current of the Controller	2 mA	7 mA
Charging Amperes	0.005 A	25 A
Occasional Short Term Over-Current (½ second) Max	50%
Total Charging Efficiency	98.9%	99.8%
Insertion Loss Resistance (Ohms)	0.001 W	0.004 W
Charge Divert Current	0 A	25 A
Charge Divert Over Current (½ Second)	50 A
Transient Surge Protections (20uS)	1500 VA
Operating and Storage Temperatures	-60° C	+60 °C
Case Dimensions 4”W x 3.75”H x 1.5”D