Schumacher Battery Charger SE 1250 Manual

The Schumacher SE 1250 is a fully automatic 12V battery charger and maintainer with a 1.25 Amp output, designed for charging and maintaining automotive, motorcycle, lawn tractor, and deep-cycle batteries. It features automatic voltage detection, multi-stage charging (bulk, absorption, float), reverse hook-up protection, and spark-proof technology. Below are key sections for safety, features, installation, operation, and troubleshooting.

1. Features at a Glance 2. Safety Instructions 3. Installation & Setup 4. Specifications 5. Controls and Indicators 6. Charging Procedure 7. Maintenance Mode 8. Care & Storage 9. Regulatory Information 10. Troubleshooting

Features at a Glance

Key components: Charger unit, Battery Clamps (red/black), AC Power Cord, LED Status Indicators.

Feature	Description
Fully Automatic Operation	Automatically selects charging voltage and switches to float/maintain mode
Multi-Stage Charging	Bulk, Absorption, and Float modes for optimal battery health
Reverse Polarity Protection	Prevents damage if clamps are connected incorrectly
Spark-Proof Technology	Safe connection; reduces risk of sparking
LED Status Indicators	Shows Charging, Complete, and Fault conditions
Compact & Portable	Lightweight design for easy transport and storage
Maintenance Mode	Keeps battery at full charge during storage
Automatic Voltage Detection	Detects 12V battery automatically
Overcharge Protection	Prevents damage from overcharging
Short-Circuit Protection	Protects charger and battery from short circuits

Safety Instructions

Read all instructions before use. Use in well-ventilated area.

Wear eye protection and avoid leaning over battery.
Do not charge frozen or damaged batteries.
Ensure charger is unplugged before connecting/disconnecting clamps.
Connect to battery first, then plug into AC outlet.
Keep charger dry and away from flammable materials.

WARNING! Risk of explosive gases. Keep sparks and flames away. Do not disassemble charger.

Installation & Setup

Unpack and inspect contents. Ensure battery is in a safe, stable location.

Prepare Battery: Clean battery terminals. Remove caps from vented batteries (if applicable).
Connect Clamps: Attach RED clamp to POSITIVE (+) battery terminal. Attach BLACK clamp to NEGATIVE (-) terminal or vehicle chassis ground.
AC Connection: Plug charger into a standard 120V AC, 60Hz outlet.
Verify Connection: LED should illuminate (Charging or Complete).

CAUTION! Ensure polarity is correct. Reverse connection may activate protection mode.

Specifications

Model: SE 1250
Input Voltage: 120V AC, 60Hz
Output Voltage: 12V DC Automatic
Charging Current: 1.25 Amps
Battery Compatibility: Standard, AGM, Gel Cell, Deep-Cycle (12V only)
Charging Stages: 3-Stage (Bulk, Absorption, Float)
Protections: Reverse Polarity, Short-Circuit, Overcharge
Indicators: LED (Charging, Complete, Fault)
Cord Length: AC Cord: 6 ft; Clamp Cables: 3 ft
Operating Temperature: 32°F to 104°F (0°C to 40°C)
Dimensions: 6.5" L x 3.5" W x 2.5" H
Weight: 1.5 lbs

Controls and Indicators

Charger operates automatically. No user controls aside from connection.

LED Indicators:

CHARGING (Red LED): Battery is being charged in Bulk or Absorption mode.
COMPLETE (Green LED): Battery is fully charged; charger is in Float/Maintenance mode.
FAULT (Red LED Flashing): Indicates reverse polarity, bad battery, or poor connection.

Note: Charger automatically switches to appropriate mode based on battery condition.

Charging Procedure

For 12V lead-acid batteries (wet, AGM, Gel Cell, Deep-Cycle).

Ensure charger is unplugged from AC outlet.
Connect clamps to battery (Red to +, Black to -).
Plug charger into AC outlet. Red CHARGING LED will illuminate.
Charger automatically progresses through stages:
- Bulk Stage: Delivers maximum current until battery reaches ~80%.
- Absorption Stage: Voltage constant, current tapers.
- Float Stage: Maintains full charge; Green COMPLETE LED lights.
When charging is complete, charger remains connected to maintain battery.
To disconnect: Unplug from AC outlet first, then remove clamps (Black first, then Red).

Tip: For deeply discharged batteries, charging may take 24 hours or more.

Maintenance Mode

After full charge, charger automatically switches to float/maintenance mode.

Green COMPLETE LED remains lit.
Charger monitors battery voltage and provides tiny pulses to keep battery at 100%.
Safe for long-term connection (weeks or months) to prevent sulfation during storage.

Note: Always monitor battery periodically. Disconnect if not in use for extended periods.

Care & Storage

Unplug and disconnect before cleaning. Store in cool, dry place.

Wipe casing with dry cloth. Do not use liquids or solvents.
Inspect cables and clamps for damage before each use.
Coil cords loosely; avoid kinks.
Store in original box or protective case if available.

CAUTION! Do not expose to rain, snow, or excessive moisture. Keep away from heat sources.

Regulatory Information

FCC Part 15: Class B digital device; complies with interference limits for residential use. UL Listed. Copyright © Schumacher Electric Corporation. All trademarks are property of their respective owners. For technical support, visit www.schumacherelectric.com or contact 1-800-621-5485.

Troubleshooting

Symptom	Possible Cause	Corrective Action
No LED lights	No AC power / Faulty outlet	Check outlet; try different outlet. Ensure charger is plugged in.
FAULT LED flashing	Reverse polarity / Bad connection	Disconnect and reconnect clamps correctly. Clean battery terminals.
CHARGING LED stays red for extended time	Deeply discharged or large battery	Allow more time (up to 48 hrs). If no progress, battery may be defective.
Battery not holding charge	Old or sulfated battery	Test battery with load tester. Replace if necessary.
Charger gets warm	Normal during charging	Ensure ventilation. If excessively hot, unplug and inspect.
Spark when connecting clamps	Charger plugged in / Circuit active	Always connect clamps BEFORE plugging into AC outlet.

Reset: Unplug charger, disconnect clamps, wait 1 minute, then reconnect properly.

Service: 1-800-621-5485; www.schumacherelectric.com