Battery Chargers

Schaefer B4800 SERIES Battery Charger

The Schaefer B4800 Series is a robust and high-capacity battery charger available in two configurations: 4kW (110Vac input models) and up to 5kW (230Vac single-phase or 3-phase input models), designed for high-demand industrial and critical infrastructure applications. With a 6U footprint, the B4800 Series requires increased airflow via external fans for effective cooling, ensuring reliable operation in challenging environments. It supports nominal battery voltages of 12Vdc, 24Vdc, 48Vdc, 60Vdc, 110Vdc, and 220Vdc, providing compatibility with a wide range of battery banks. Flexible mounting options, including chassis mount, wall mount, and 19" rackmount via a 6U subrack, facilitate easy integration. Additionally, the B4800 Series supports parallel configurations for high-power or redundant systems (N+1 or A+B configurations). Optional features, including additional electrical protection, monitoring, conformal coating, and enhanced mechanical strength, offer increased resilience in demanding industrial settings. 

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Schaefer B4800 SERIES Battery Charger

Features

  • High Power Capability: Reliable 4KW / 5KW battery charger designed for industrial and critical infrastructure applications.
  • AC Input: options for 1-Phase or 3-Phase supply
  • DC Output Voltages: Compatible with a wide range of battery voltages, including 12Vdc, 24Vdc, 48Vdc, 60Vdc, 110Vdc, and 220Vdc.
  • Flexible Installation: Offers multiple mounting options, including wall, or 19" rackmount via a 6U subrack, and options for parallel / redundant system arrangements.
  • Durable Construction: Optional features include conformal coating, enhanced mechanical strength, and additional electrical protection for increased resilience.
Specifications
INPUT
Input voltage 1ph 115/230Vac 3ph 200/400/480Vac See selection table Units will turn off with under or over input voltage.
No-load input power 3-6W model (series dependant)
Inrush current AC input limited by thermistor
Switch on time 1-2 seconds.
Input Options Option au: Autoranging for 115/230Vac input Option pr: Power OK via relay contacts
ENVIRONMENTAL
Operating temperature -20°C to +75°C (optional -40 to 75C)
Load derating Derate 2.5% per °C, from +55°C to 75°C
Cooling H: Heatsink - natural convection F: Fan - increased airflow recommended TF: Temperature controlled Fan included See selection table
Environment Options Option c: Extended temperature range to -40°C
Storage temperature -40°C to +85°C
Humidity Up to 95% RH, non-condensing
INPUT
Input voltage 1ph 115/230Vac 3ph 200/400/480Vac See selection table Units will turn off with under or over input voltage.
No-load input power 3-6W model (series dependant)
Inrush current AC input limited by thermistor
Switch on time 1-2 seconds.
Input Options Option au: Autoranging for 115/230Vac input Option pr: Power OK via relay contacts
STANDARDS
EMI standards acc. to EN61000-6-4 class A, optionally class B
Immunity standards acc. to EN61000-6-2
C-Tick AS/NZS CISPR11: 2002 Group1 Class A
Safety / Construction acc. to EN60950-1 / EN50178
Protection category IP20 acc. to EN60529 NEMA or others on request
PROTECTION
Overload protection Current limited at 105%–110% of full load.
Overvoltage protection OVP switches off module with automatic return to operation
Protection Options Option i: Inrush Current Limiting Option sd: Reverse polarity protection for DC input by Series Diode
MTBF 100Khrs to 140Khrs at 40°C acc. to MIL-HDBK-217E (notice 1)
MECHANICAL
Mounting See technical illustrations Eurocassette, pluggable module for 19" subrack Option w: Wall Mounting Option cha: Chassis Mounting
Dimensions See Technical illustration
Connector H15 acc. to DIN 41612 H15 and high current connectors for I > 50A, or terminals / bolts / bars
Mechanical Options Option ms: Increased Mechanical Strength Option t: Tropical protection
19" Rack Mounting Options Subrack Height 3U, 5U, 6U Wiring, Front Panels Accessories: Fuses, MCBs, Mains on/off switch Contact Powerbox for rack configuration
Selection Table
INPUT 115VAC ± 20% OUTPUT AMPS INPUT 230VAC + 5% - 20% INPUT 3X200VAC +15% - 20% INPUT 3X400VAC +15% - 20% INPUT 3X480VAC +15% - 20% OUTPUT AMPS COOLING HEATSINK FAN BATTERY CHARGER VOLTAGE VOLTAGE ADJ. RANGE
B4861 2203) B4881 B4861V B4881V B4891V 220 F 12 12-16
B4862 122 B4882 B4862V B4882V B4892V 140 F 24 24-32
B4864 62 B4884 B4864V B4884V B4894V 70 F 48 48-64
B4866 50 B4886 B4866V B4886V B4896V 60 F 60 60-80
B4867 28 B4887 B4867V B4887V B4897V 34 F 110 110-145
B4868 14 B4888 B4868V B4888V B4898V 18 F 220 220-290

Cooling
H: Heatsink - natural convection
F: Fan - increased airflow recommended
TF: Temperature controlled Fan included
See selection table

   
Model configuration options: Add the options to the model number, eg. B4884-dd-dr-cs Options for Input, Output, Environmental and Mechanical follow.
19" Rack Mounting Options Subrack Height 3U, 5U, 6U Wiring, Front Panels Accessories: Fuses, MCBs, Mains on/off switch Contact Powerbox for rack configuration
OPTIONS INPUT
Option “i” (inrush current limiting): A thermistor is connected in series with the
input lines which changes its resistance from high to low when it gets hot. It does
not reduce the current surge if the input power is interrupted for a short period of
time not allowing the thermistor to cool down. Thermistors are fitted as standard
to all mains input models except for 1-phase input of models > 2.5kW.
Thermistors are available up to 45A. For higher input current an electronic inrush
current limitation can be offered.
Option “ie” electronic inrush current limiting An electronic circuit limits the inrush current.
Option “sd” (series diode): A series diode protects the module against input
voltage of wrong polarity (additional power losses).
Option “ad” (anti-parallel diode): To avoid the power losses of a series diode a diode is
provided with opposite polarity in parallel to the input blowing an internal or external
fuse if the module is connected to a supply with wrong polarity.
Option “au” (auto-ranging) For standard dual AC input models the range of
115/230Vac is to be selected by connecting the input line to different pins on the
connector. With auto-ranging the unit senses the input voltage and provides
automatically the correct connection.
Option “p” (power fail): A signal (logic or relay) is given if the input voltage (AC or
DC) drops below the specified limit. In AC input units we sense the rectified input
voltage so that a power fail alarm will not be triggered if at light loads mains
power returns before the input capacitors are substantially discharged.
Option “r” (relay): A relay instead of a logic signal is provided for failure indication.
OUTPUT
Option “dd” (decoupling diode): For redundant operation the outputs of two or
more units are paralleled behind de-coupling diodes so that an internal fault of
one module does not affect the operation of the others. These diodes cause power
losses.
Option “cs” (active current sharing): An additional control circuit provides active
current sharing via an interconnecting wire between converters that operate in
parallel. Active current sharing should be used for multi-output units operating in
parallel.
Option “csi” (current sharing interrupt): Option "csi" will effect the removal of the
"cs" signal. Should there be an instance where a unit is not supplying the load,
then the effect of its "cs" signal is removed, and the load voltage is unaffected by
this condition.
Option “h1” (inhibit): A terminal connected to the negative input line also shuts off the
converter. This can also be used in conjunction with a thermal trip which shuts the unit
down.
Option “h2” (inhibit): Operation of the unit is inhibited if a voltage signal
(5V/10mA) is applied in reference to the negative line of the (main) output.
Option “rco” (reducing current limiting at over temperature) A circuit reduces the
current limiting level at higher temperature (to be specified).
Option “d” (DC-ok, one output): A logic signal is given if the output voltage (main
output in multi-output systems) is below the specified limit.
Option “m” (DC-ok, all outputs): In multi-output systems a logic signal is provided
if the voltage of any output is below the specified limit.
Option “ac” (AC ok) A logic signal connected to relay contacts is given if the
output voltage of an inverter is below the specified limit.
Option "y" (sys-reset): This logic signal is a combination of power fail and DC-ok
as specified for VME systems.
Option "r" (relay): A relay instead of a logic signal is provided for failure
indication.
CHARGER PROGRAMMING
Option "tc" Temperature compensated charging voltage(sensor not included)
Option "ts1" Temperature sensor, not interchangeable due to fixed resistor values
Option "ts2" Interchangeable, IC controlled
Option "ch1" Automatic selection of charging characteristic (float / equalize charge) with timer
Option "ch2" Additionally: Manual selection of charging characteristic
Option "ch3" Additionally: Boost charge operation (manually activated with time delayed return to normal operation)
ENVIRONMENT
Option "t" (tropical protection):The unit is given additional protection by a heavy coat of varnish on the printed circuit board(s) and components.
Option "c" (extended temperature range):The circuit is designed and tested for operation at an ambient temperature as low as –40 °C.
Option "ms" (increased mechanical strength): Screws are secured by Locktite and heavy components are fastened by ties and/or glue. Modules with the "ms" option meet the standard EN61373 regarding shock and vibration.
MECHANICS
Standard mounting "Eurocassette" pluggable module for 19" sub-racks 8
Option "w" (wall mounting): Module is screwed against a mounting plate for installation in a cabinet. The load connections are typically a terminal block.
Option "cha" (chassis mount) Module is designed for installation to a structure or within cabinet. Screw type connectors are supplied with the module.
Option "din" (DIN rail mount) Module is designed for DIN rail mounting to a structure or within Cabinet. Screw type connectors are supplied with the module.
Technical Illustrations
INPUT
Input voltage 1ph 115/230Vac 3ph 200/400/480Vac See selection table Units will turn off with under or over input voltage.
No-load input power 3-6W model (series dependant)
Inrush current AC input limited by thermistor
Switch on time 1-2 seconds.
Input Options Option au: Autoranging for 115/230Vac input Option pr: Power OK via relay contacts
ENVIRONMENTAL
Operating temperature -20°C to +75°C (optional -40 to 75C)
Load derating Derate 2.5% per °C, from +55°C to 75°C
Cooling H: Heatsink - natural convection F: Fan - increased airflow recommended TF: Temperature controlled Fan included See selection table
Environment Options Option c: Extended temperature range to -40°C
Storage temperature -40°C to +85°C
Humidity Up to 95% RH, non-condensing
INPUT
Input voltage 1ph 115/230Vac 3ph 200/400/480Vac See selection table Units will turn off with under or over input voltage.
No-load input power 3-6W model (series dependant)
Inrush current AC input limited by thermistor
Switch on time 1-2 seconds.
Input Options Option au: Autoranging for 115/230Vac input Option pr: Power OK via relay contacts
STANDARDS
EMI standards acc. to EN61000-6-4 class A, optionally class B
Immunity standards acc. to EN61000-6-2
C-Tick AS/NZS CISPR11: 2002 Group1 Class A
Safety / Construction acc. to EN60950-1 / EN50178
Protection category IP20 acc. to EN60529 NEMA or others on request
PROTECTION
Overload protection Current limited at 105%–110% of full load.
Overvoltage protection OVP switches off module with automatic return to operation
Protection Options Option i: Inrush Current Limiting Option sd: Reverse polarity protection for DC input by Series Diode
MTBF 100Khrs to 140Khrs at 40°C acc. to MIL-HDBK-217E (notice 1)
MECHANICAL
Mounting See technical illustrations Eurocassette, pluggable module for 19" subrack Option w: Wall Mounting Option cha: Chassis Mounting
Dimensions See Technical illustration
Connector H15 acc. to DIN 41612 H15 and high current connectors for I > 50A, or terminals / bolts / bars
Mechanical Options Option ms: Increased Mechanical Strength Option t: Tropical protection
19" Rack Mounting Options Subrack Height 3U, 5U, 6U Wiring, Front Panels Accessories: Fuses, MCBs, Mains on/off switch Contact Powerbox for rack configuration
INPUT 115VAC ± 20% OUTPUT AMPS INPUT 230VAC + 5% - 20% INPUT 3X200VAC +15% - 20% INPUT 3X400VAC +15% - 20% INPUT 3X480VAC +15% - 20% OUTPUT AMPS COOLING HEATSINK FAN BATTERY CHARGER VOLTAGE VOLTAGE ADJ. RANGE
B4861 2203) B4881 B4861V B4881V B4891V 220 F 12 12-16
B4862 122 B4882 B4862V B4882V B4892V 140 F 24 24-32
B4864 62 B4884 B4864V B4884V B4894V 70 F 48 48-64
B4866 50 B4886 B4866V B4886V B4896V 60 F 60 60-80
B4867 28 B4887 B4867V B4887V B4897V 34 F 110 110-145
B4868 14 B4888 B4868V B4888V B4898V 18 F 220 220-290

Cooling
H: Heatsink - natural convection
F: Fan - increased airflow recommended
TF: Temperature controlled Fan included
See selection table

   
Model configuration options: Add the options to the model number, eg. B4884-dd-dr-cs Options for Input, Output, Environmental and Mechanical follow.
19" Rack Mounting Options Subrack Height 3U, 5U, 6U Wiring, Front Panels Accessories: Fuses, MCBs, Mains on/off switch Contact Powerbox for rack configuration
OPTIONS INPUT
Option “i” (inrush current limiting): A thermistor is connected in series with the
input lines which changes its resistance from high to low when it gets hot. It does
not reduce the current surge if the input power is interrupted for a short period of
time not allowing the thermistor to cool down. Thermistors are fitted as standard
to all mains input models except for 1-phase input of models > 2.5kW.
Thermistors are available up to 45A. For higher input current an electronic inrush
current limitation can be offered.
Option “ie” electronic inrush current limiting An electronic circuit limits the inrush current.
Option “sd” (series diode): A series diode protects the module against input
voltage of wrong polarity (additional power losses).
Option “ad” (anti-parallel diode): To avoid the power losses of a series diode a diode is
provided with opposite polarity in parallel to the input blowing an internal or external
fuse if the module is connected to a supply with wrong polarity.
Option “au” (auto-ranging) For standard dual AC input models the range of
115/230Vac is to be selected by connecting the input line to different pins on the
connector. With auto-ranging the unit senses the input voltage and provides
automatically the correct connection.
Option “p” (power fail): A signal (logic or relay) is given if the input voltage (AC or
DC) drops below the specified limit. In AC input units we sense the rectified input
voltage so that a power fail alarm will not be triggered if at light loads mains
power returns before the input capacitors are substantially discharged.
Option “r” (relay): A relay instead of a logic signal is provided for failure indication.
OUTPUT
Option “dd” (decoupling diode): For redundant operation the outputs of two or
more units are paralleled behind de-coupling diodes so that an internal fault of
one module does not affect the operation of the others. These diodes cause power
losses.
Option “cs” (active current sharing): An additional control circuit provides active
current sharing via an interconnecting wire between converters that operate in
parallel. Active current sharing should be used for multi-output units operating in
parallel.
Option “csi” (current sharing interrupt): Option "csi" will effect the removal of the
"cs" signal. Should there be an instance where a unit is not supplying the load,
then the effect of its "cs" signal is removed, and the load voltage is unaffected by
this condition.
Option “h1” (inhibit): A terminal connected to the negative input line also shuts off the
converter. This can also be used in conjunction with a thermal trip which shuts the unit
down.
Option “h2” (inhibit): Operation of the unit is inhibited if a voltage signal
(5V/10mA) is applied in reference to the negative line of the (main) output.
Option “rco” (reducing current limiting at over temperature) A circuit reduces the
current limiting level at higher temperature (to be specified).
Option “d” (DC-ok, one output): A logic signal is given if the output voltage (main
output in multi-output systems) is below the specified limit.
Option “m” (DC-ok, all outputs): In multi-output systems a logic signal is provided
if the voltage of any output is below the specified limit.
Option “ac” (AC ok) A logic signal connected to relay contacts is given if the
output voltage of an inverter is below the specified limit.
Option "y" (sys-reset): This logic signal is a combination of power fail and DC-ok
as specified for VME systems.
Option "r" (relay): A relay instead of a logic signal is provided for failure
indication.
CHARGER PROGRAMMING
Option "tc" Temperature compensated charging voltage(sensor not included)
Option "ts1" Temperature sensor, not interchangeable due to fixed resistor values
Option "ts2" Interchangeable, IC controlled
Option "ch1" Automatic selection of charging characteristic (float / equalize charge) with timer
Option "ch2" Additionally: Manual selection of charging characteristic
Option "ch3" Additionally: Boost charge operation (manually activated with time delayed return to normal operation)
ENVIRONMENT
Option "t" (tropical protection):The unit is given additional protection by a heavy coat of varnish on the printed circuit board(s) and components.
Option "c" (extended temperature range):The circuit is designed and tested for operation at an ambient temperature as low as –40 °C.
Option "ms" (increased mechanical strength): Screws are secured by Locktite and heavy components are fastened by ties and/or glue. Modules with the "ms" option meet the standard EN61373 regarding shock and vibration.
MECHANICS
Standard mounting "Eurocassette" pluggable module for 19" sub-racks 8
Option "w" (wall mounting): Module is screwed against a mounting plate for installation in a cabinet. The load connections are typically a terminal block.
Option "cha" (chassis mount) Module is designed for installation to a structure or within cabinet. Screw type connectors are supplied with the module.
Option "din" (DIN rail mount) Module is designed for DIN rail mounting to a structure or within Cabinet. Screw type connectors are supplied with the module.

Find the Right Model

Model Number Input Voltage (Vac) Output Voltage (Vdc) Output Current (A)
product variant B4861 115Vac ± 20 % 50/60Hz 12Vdc (Adj. 12 - 16Vdc) 220A
product variant B4862 115Vac ± 20 % 50/60Hz 24Vdc (Adj. 24 - 32Vdc) 122A
product variant B4864 115Vac ± 20 % 50/60Hz 48Vdc (Adj. 48 - 64Vdc) 62A
product variant B4866 115Vac ± 20 % 50/60Hz 60Vdc (Adj. 60 - 80VDc) 50A
product variant B4867 115Vac ± 20 % 50/60Hz 110Vdc (Adj. 110 - 145VDc) 28A
product variant B4868 115Vac ± 20 % 50/60Hz 220Vdc (Adj. 220 - 290Vdc) 14A
product variant B4881 230Vac +15%/-20% 50/60Hz 12Vdc (Adj. 12 - 16Vdc) 220A
product variant B4882 230Vac +15%/-20% 50/60Hz 24Vdc (Adj. 24 - 32Vdc) 140A
product variant B4884 230Vac +15%/-20% 50/60Hz 48Vdc (Adj. 48 - 64Vdc) 70A
product variant B4886 230Vac +15%/-20% 50/60Hz 60Vdc (Adj. 60 - 80VDc) 60A
product variant B4887 230Vac +15%/-20% 50/60Hz 110Vdc (Adj. 110 - 145VDc) 34A
product variant B4888 230Vac +15%/-20% 50/60Hz 220Vdc (Adj. 220 - 290Vdc) 18A
product variant B4861V 3 x 200Vac +15%/-20% 50/60Hz 12Vdc (Adj. 12 - 16Vdc) 220A
product variant B4862V 3 x 200Vac +15%/-20% 50/60Hz 24Vdc (Adj. 24 - 32Vdc) 140A
product variant B4864V 3 x 200Vac +15%/-20% 50/60Hz 48Vdc (Adj. 48 - 64Vdc) 70A
product variant B4866V 3 x 200Vac +15%/-20% 50/60Hz 60Vdc (Adj. 60 - 80VDc) 60A
product variant B4867V 3 x 200Vac +15%/-20% 50/60Hz 110Vdc (Adj. 110 - 145VDc) 34A
product variant B4868V 3 x 200Vac +15%/-20% 50/60Hz 220Vdc (Adj. 220 - 290Vdc) 18A
product variant B4881V 3 x 400Vac +15%/-20% 50/60Hz 12Vdc (Adj. 12 - 16Vdc) 220A
product variant B4882V 3 x 400Vac +15%/-20% 50/60Hz 24Vdc (Adj. 24 - 32Vdc) 140A
product variant B4884V 3 x 400Vac +15%/-20% 50/60Hz 48Vdc (Adj. 48 - 64Vdc) 70A
product variant B4886V 3 x 400Vac +15%/-20% 50/60Hz 60Vdc (Adj. 60 - 80VDc) 60A
product variant B4887V 3 x 400Vac +15%/-20% 50/60Hz 110Vdc (Adj. 110 - 145VDc) 34A
product variant B4888V 3 x 400Vac +15%/-20% 50/60Hz 220Vdc (Adj. 220 - 290Vdc) 18A
product variant B4891V 3 x 480Vac +10%/-15% 50/60Hz 12Vdc (Adj. 12 - 16Vdc) 220A
product variant B4892V 3 x 480Vac +10%/-15% 50/60Hz 24Vdc (Adj. 24 - 32Vdc) 140A
product variant B4894V 3 x 480Vac +10%/-15% 50/60Hz 48Vdc (Adj. 48 - 64Vdc) 70A
product variant B4896V 3 x 480Vac +10%/-15% 50/60Hz 60Vdc (Adj. 60 - 80VDc) 60A
product variant B4897V 3 x 480Vac +10%/-15% 50/60Hz 110Vdc (Adj. 110 - 145VDc) 34A
product variant B4898V 3 x 480Vac +10%/-15% 50/60Hz 220Vdc (Adj. 220 - 290Vdc) 18A

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