A77D/A77DE (Micro Processor Controlled SCR Charger)

  • Reliably engineered for high – demanding DC power applications
  • Available in DC outputs 24, 48, 130, and 260VDC with currents 6-500Amps
  • Powered by Microprocessor Controlled SCR technology
  • Features an easy to read LCD display and LED based alarms indicators
  • Supports DNP3, Modbus, IEC 61850 and SNMP3 which enables a user-friendly web browser-based configuration interface
  • Designed to meet NEMA PE5 and UL 1012 safety standards

Please contact our sales team for special input-output configurations.

 Data Sheet

Instruction Manuals
A77 Series Instruction Manual
Instruction Manuals for Communication Cards

IEC 61850 Protocol

DNP 3.0 Interface

MODBUS Interface
MODBUS RTU Interface
SNMP Interface
21X MIB File
Alarm Relay Package
IEC-61204-7 Certified

Hydrogen Detection Alarm Interface

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•   Microprocessor Controlled SCR Technology

•   A77D - Filtered

•   A77DE - Battery Eliminator

•   Automatic AC Voltage Compensation

•   AC & DC Surge Protection (MOV)

•   AC & DC Breaker

•   Temperature Compensation - Adjustable (1-5 mV /cell/°C)

•   Float / Equalize Mode Switch

•   Digital Float and Equalize Adjustments

•   Digital Current Limit Adjustment 50 to 110%

•   ±0.25% DC Voltage Regulation

•   SCR Failure Detection

•   Battery Continuity Test

•   Load Sharing

•   Remote Equalize

•   Over Temperature Protection

•   LCD Display:

                DC Voltage and Current


                Unit Temperatures

•   Advanced Data Logging (Micro SD)

•   LED Indicators:

                Float / Equalize

                AC Failure

                AC ON

                Summary Alarm

                Charger Failure

                Low DC Current

                Overload / Current Limit

                Low DC Voltage

                End of Discharge

                High DC Voltage

                High DC Voltage Shutdown

                Positive & Negative Ground Detection

•   Remote Annunciation Form “C” Contacts:

                AC Failure

                Summary Alarm

                (See Optional Accessories For Additional Alarm Contacts)

•   Alarms Latching / Non-Latching

•   Equalize Timer - adjustable from 1-255 hours with five selectable modes of operation (manual, automatic every 7,    

    14 or 30 days and equalize after sensing a low DC voltage)

•   UL 1012, CUL, IBC & ABS

•   5 Year Warranty

•   2 - Pole High Interrupting Capacity AC Breaker 65KAIC @ 240VAC / 35KAIC @ 480VAC / 18KAIC @ 600 VAC

•   2 - Pole High Interrupting Capacity AC Breaker 100KAIC @ 240VAC / 65KAIC @ 480VAC / 25 KAIC @ 600VAC

•   3-Pole High Interrupting Capacity AC Breaker* 65KAIC @ 240 VAC/ 25KAIC @ 480 VAC / 18KAIC @ 600 VAC

•   3-Pole High Interrupting Capacity AC Breaker* 100KAIC @ 240 VAC/ 65KAIC @ 480 VAC / 25KAIC @ 600 VAC

•   DC Breaker 10KAIC

•   Equalize Fan Control Relay

•   Reverse Polarity Protection & LED

•   Copper Ground Bus Bar

•   Lightning Arrestor

•   Blocking Diode

•   External Temperature Probe 22ft

•   External Temperature Probe 100ft

•   I.D Tags - White text on black background

•   I.D Tags - Black text on white background

•   Heat Shrink Wire Markers with Electrical Schematic

•   Discrete Alarm Relays

             Positive Ground

             Negative Ground

             High DC Volts

             Charger Failure

             Low DC Volts

             Low DC Amps

             Battery End of Discharge

             High Voltage Shutdown

•   OSHPD Certification Label (consult factory for Anchor Kits)

•   IBC Certification Label (consult factory for Anchor Kits)

•   IEC 61850 Ethernet

•   DNP 3.0 Communications RS232/RS485/Ethernet

•   Modbus Communications RS232/RS485/Ethernet

•   Modbus RTU RS232/RS485

•   SNMP & Web Browser (Ethernet)


AC Input Operating Range Voltage

Voltage range:  +10, -12% from nominal

Frequency range: 60 Hz ±5%

(50Hz Consult Factory)

Single Phase Voltages:

120, 208, 240, 480 or 600 VAC

(Tap selectable 120/208/240 on units up to 25 amp output. All other units must specify single input voltage). Consult factory for other voltages.

Three Phase Voltages:

208, 240, 480 or 600 VAC

Consult factory for other voltages.

DC Output

24, 48, 130, 260 VDC

6 to 500 amps

DC Voltage Regulation Steady State

± 0.25% of setting from no load to full load over the specified input voltage, frequency and ambient temperature ranges.

Data Logging

A77 Battery Charger is equipped with data logging capability on an internal Micro-SD Card. It logs and stores data of Event-Driven and Time-Interval-Driven Events. The charger’s data-log file does not need proprietary software to examine the data; it could be viewed and easily formatted with many popular spreadsheet programs.

Dynamic Response (On Battery)

Voltage transient < ±5% over a step change

in the load from 20% to 100%

Recovery Time < 200 mS

Audible Noise

Less than 65dBA at any point 5 feet from any vertical surface of the unit.

Load Sharing

Identical La Marche A77 units, when           connected in parallel, are capable of sharing the DC load within ±5% for individual unit outputs greater than 5% of the rated output.


Form “C” Alarm Contacts

With optional Communications Card:

•  Connect to SCADA System

•  Web Monitoring

•  Alarm / Notification E-mails









Current Walk-in

The output current will gradually increase after the charger is turned on, eliminating surges and overshoot.

Current Limit

Electronic Current-Limiting  Control Circuitry provides a digitally adjustable limit from  50 to 110% of the rated output  current of the charger,

Factory set at 110%.

AC Breaker

Single Phase units are equipped with a 2-pole circuit breaker.  Three Phase units are equipped

with a 3-pole circuit breaker.

DC Breaker

Standard units are equipped with a 2-pole circuit breaker.


Operating Temperature

0 to 50°C (32 to 122°F)

Storage Temperature

-40 to 85°C (-40 to 185°F)

Relative Humidity

0 to 95% (non-condensing)


Convection Cooled


NEMA Type 1

Consult factory for other enclosure ratings.


Overall dimensions and weight are listed on the last page. When space requirements are critical, please consult the factory. Case specifications are subject to change.


Floor, wall or rack mounting is available; see enclosure specifications on page 4 for details.


Pretreated with a seven stage iron phosphate wash, sealer and deionized rinse. Then coated with an environmentally safe and durable ANSI 61 gray Polyester TGIC Minite powder finish.



UL/CUL 1012

EN 55011


FCC Part 15

IEEE / ANSI C37. 90.1

IEC 60255-22-3

IEC 61000-4


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