Is the 43 Series a 12V or 24V supply?
Both are available. The 12V family is rated at DC 13.5V and the 24V family at DC 27V. Select the family that matches the load and battery system.
EPS-SD/SP/ST 43 Series
43 Series EPS Emergency Power Supply
Sanyi Power® 43 Series EPS emergency power supplies include EPS-SD-4301, EPS-SP-4303, EPS-ST-4304, EPS-ST-4308 and EPS-ST-4310. The family provides 12V/24V options, 1/3/4/8/10 output circuits, battery float charging and automatic mains/battery switchover for emergency-lighting and security backup selection.
Certifications
3CCE
Applications
EPSemergencyfire safetybattery backup43 Series EPS power supply12V emergency power supply24V EPS power supplymulti-output backup power supplysecurity system backup PSUbattery float charger power supplyEPS-SD-4301EPS-SP-4303EPS-ST-4304EPS-ST-4308EPS-ST-4310
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Inquire About This Product →Features
- EPS-SD-4301 / EPS-SP-4303 / EPS-ST-4304 / EPS-ST-4308 / EPS-ST-4310
- 12V family rated at DC 13.5V; 24V family rated at DC 27V
- 1/3/4/8/10 output configurations
- Built-in battery float charging and automatic mains/battery switchover
- Built-in EMI filter with overload and charging protection
Specifications
| Models | EPS-SD-4301 / EPS-SP-4303 / EPS-ST-4304 / EPS-ST-4308 / EPS-ST-4310 |
| Output Circuits | 1 / 3 / 4 / 8 / 10 |
| Input Range | AC 100-240V, 50/60Hz |
| 12V Family Output | DC 13.5V; 1.5A / 3A / 5A / 10A depending on model |
| 24V Family Output | DC 27V; 1A / 1.5A / 4A / 5A depending on model |
| Battery Management | Float charging; automatic battery supply when mains fails |
| Operating Temperature | -10°C to 60°C (derate at elevated temperature per datasheet) |
How to select a 43 Series EPS power supply
The 43 Series is intended for low-voltage DC emergency-lighting and security backup applications. Start with system voltage, total load current, required output circuits and battery requirements, then verify the exact model datasheet. It should not be selected as a substitute for a high-power AC EPS or UPS by name alone.
Four inputs needed for engineering selection
- 1
Choose the voltage system
The 12V family is rated at DC 13.5V and the 24V family at DC 27V. Loads, battery and controller must use a compatible voltage system.
- 2
Calculate load current
List the steady-state, startup and abnormal-condition current for every circuit and apply the project margin. Confirm final limits in the model datasheet.
- 3
Choose output circuits
The family provides 1, 3, 4, 8 and 10-output configurations. Multiple outputs simplify zoning and troubleshooting, but every circuit still requires a load calculation.
- 4
Check battery and environment
Specify battery type, capacity, target backup time, mounting space and ambient temperature. Apply datasheet derating at elevated temperature.
Confirmed 43 Series scope
- Models
- EPS-SD-4301 / EPS-SP-4303 / EPS-ST-4304 / EPS-ST-4308 / EPS-ST-4310
- Input
- AC 100–240V, 50/60Hz
- Output families
- 12V family: DC 13.5V; 24V family: DC 27V
- Output circuits
- 1 / 3 / 4 / 8 / 10
- Battery management
- Float charging and automatic transfer to battery when mains fails
Typical requirement areas
- Low-voltage DC backup for emergency lighting
- Backup-power evaluation for access control, CCTV and alarm systems
- Security control boxes requiring zoned multi-output distribution
- Equipment requiring battery float charging and mains/battery transfer
Datasheet basis and test conditions
These engineering references come from the available EPS-SD-4301, EPS-SP-4303, EPS-ST-4304, EPS-ST-4308 and EPS-ST-4310 datasheets.
- EPS-SD-4301
- 1 output: 13.5V / 1.5A / 20.25W, or 27V / 1A / 27W; charging current 0–0.8A.
- EPS-SP-4303
- 3 outputs: 13.5V / 3A / 40.5W, or 27V / 1.5A / 40.5W; charging current 0–0.8A.
- EPS-ST-4304
- 4 outputs: 13.5V / 5A / 67.5W, or 27V / 4A / 108W; charging current 0–0.8A.
- EPS-ST-4308
- 8 outputs: 13.5V / 10A / 135W, or 27V / 5A / 135W; charging current 0–1A.
- EPS-ST-4310
- 10 outputs: 13.5V / 10A / 135W, or 27V / 5A / 135W; charging current 0–1A.
- Standard test condition
- Unless otherwise stated, parameters are measured at AC 230V input, rated load and 25°C ambient temperature.
- Ripple and noise
- The datasheets state 120mVp-p maximum, measured at 20MHz with a 12-inch twisted pair terminated by 0.1μF and 47μF parallel capacitors.
- Typical efficiency
- The available 43 Series datasheets state 82% typical efficiency; confirm the exact model and operating condition.
- Protection and recovery
- The datasheets list short-circuit, overload and charging overvoltage/undervoltage protection, with recovery as specified after the fault is removed.
- EMC system boundary
- The supply is a system component; final EMC must still be confirmed with the terminal equipment, wiring, load, enclosure and grounding.
Datasheet revisions and project requirements can change. Final selection, compliance and production parameters require the latest model datasheet and engineering confirmation.
43 Series FAQ
How many output circuits are available?
The current family covers 1, 3, 4, 8 and 10-output configurations. Confirm per-circuit current and wiring in the exact model datasheet.
How long will the battery backup last?
Runtime depends on battery capacity, load power, wiring loss, battery condition and temperature. A load list and target runtime are required before sizing the battery.
Can it directly replace a UPS?
Not by name alone. The 43 Series is a low-voltage DC backup solution; a UPS can have a different output form, transfer method and load profile.
What should I provide for a quotation?
Provide input voltage, load voltage and total current, number of outputs, battery type and capacity, target runtime, mounting, ambient temperature and quantity.
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43 Series EPS Emergency Power Supply
EPS-SD/SP/ST 43 Series