SR81 solar water heater controller is the updated version of SR868C8, featuring 0.1°C temperature accuracy, 10 push buttons with separate keypad, 5 optional variants, FRT flow meter integration, 1.5KW/3KW/4KW heating options and comprehensive safety functions for solar thermal systems.
The SR81 solar water heater controller is an updated version of the SR868C8, featuring high-precision temperature measurement with ±0.1°C accuracy. Equipped with 10 push buttons on the front cover and a separate keypad, this controller offers intuitive operation for diverse solar thermal system applications.
With 5 optional variant versions available, the SR81 provides flexible configuration options to meet different installation requirements. The separate keypad design enhances installation flexibility, making it suitable for various mounting scenarios.
Built with industrial-grade components and enclosed in a durable ABS plastic housing with IP41 protection, the SR81 ensures reliable performance even in demanding environmental conditions. Its wall-mounting design simplifies installation, while the low power consumption (<2.5W) makes it energy-efficient for long-term operation.
High-precision temperature measurement: ±0.1°C accuracy for precise control
10 push buttons on front cover for intuitive operation
Separate keypad design for flexible installation (120mm × 120mm × 18mm)
5 variant versions available to meet different application needs
Wide collector temperature range: -10°C ~ 220°C
Tank temperature range: 0°C ~ 110°C
Supports up to 3 pumps for circulation and system control
Multiple power variants: 1.5KW, 3KW, and 4KW versions available
Flow meter integration: 1× Rotary vane type electron flow meter (FRT)
Multi-sensor support: 5 sensors including Pt1000 and NTC10K sensors
4 relay outputs for circulation pump and backup heating control
IP41 protection rating for reliable performance in various environments
| Parameter | Specification |
|---|---|
| Model | SR81 Solar Water Heater Controller |
| Type | Updated version of SR868C8 |
| Temperature Measurement Accuracy | ±0.1°C |
| Collector Temperature Range | -10°C ~ 220°C |
| Tank Temperature Range | 0°C ~ 110°C |
| Max. Number of Collectors | 1 |
| Max. Number of Storage Tanks | 1 |
| Max. Number of Relays | 4 |
| Max. Number of Sensors | 5 |
| Max. Number of Visualization Systems | 1 |
| Flow Meter | 1× Rotary vane type electron flow meter (FRT) |
| Keypad Dimensions | 120mm × 120mm × 18mm |
| Controller Dimensions (1.5KW) | 187mm × 128mm × 46mm |
| Controller Dimensions (3KW/4KW) | 218mm × 165mm × 55mm |
| Power Supply | AC 100-240V, 50-60Hz |
| Power Consumption | < 2.5W |
| Rated Impulse Voltage | 2.5KV |
| Housing Material | Plastic ABS |
| Protection Type | IP41 |
| Mounting | Wall mounting |
| Suitable Pump Power | Up to 3 pumps can be connected |
| Backup Heating (HK) Power (1.5KW) | 1pc < 1.5KW |
| Backup Heating (HK) Power (3KW) | 1pc < 3KW |
| Backup Heating (HK) Power (4KW) | 1pc < 4KW |
| Collector Sensor | 1× Pt1000 (≤500°C) with silicon cable (≤280°C) |
| Tank Sensors | 4× NTC10K B3950 (≤135°C) with PVC cable (≤105°C) |
| Output Relays | 4 relays for circulation pump and backup heating |
| Electromagnetic Relays | 3× Max. current 2A |
| HK Relay (1.5KW) | 10A |
| HK Relay (3KW) | 15A |
| HK Relay (4KW) | 20A |
| Ambient Temperature | -10°C ~ 50°C |
| Water Proof Grade | IP41 |
DATE - Date setting function
Timed heat - Backup heating with time scheduling
Circle - Hot water circulation function
LOAD - Loading tank setup function
COL - Collector 1 control function
PUMP - Pump control mode selection
COOL - Cooling function
AUX - Auxiliary function
MAN - Manual operation mode
BLPR - Blocking protection function
OTDI - Thermal disinfection function for hygienic water
FS - Flow meter type selection
UNIT - Celsius/Fahrenheit temperature unit switch
RST - Factory reset function
PASS - Password setting for security
Holiday function for special schedule management
Screen Protection (screen saver) to extend display life
Trouble Protection system for safe operation
Trouble Checking with error diagnostics for easy troubleshooting
The SR81 solar controller is designed for solar thermal systems requiring high-precision temperature control and reliable performance. With support for up to 5 sensors, 4 relays, and 3 pumps, it is suitable for residential solar water heating systems, small commercial solar thermal installations, and specialized solar heating applications requiring flow measurement and backup heating capabilities.
| Item | Content |
|---|---|
| SEO Title | sr81-solar-water-heater-controller-sr868c8-updated-version-high-precision-control |
| Keywords | SR81 solar water heater controller,SR868C8 updated version,0.1°C accuracy solar controller,separate keypad solar controller,5 variant solar controller,FRT flow meter solar controller,high precision solar controller,1.5KW 3KW 4KW solar controller,IP41 solar controller,intelligent solar heater controller |
| Meta Description | SR81 solar water heater controller is the updated version of SR868C8, featuring 0.1°C temperature accuracy, 10 push buttons with separate keypad, 5 optional variants, FRT flow meter integration, 1.5KW/3KW/4KW heating options and comprehensive safety functions for solar thermal systems. |
| Tag Labels | Solar Water Heater Controller|SR81|SR868C8 Updated Version|0.1°C High Precision|10 Push Buttons|Separate Keypad|5 Variants|FRT Flow Meter|1.5KW 3KW 4KW|IP41 Protection |
| Static Page Name | SR81_Solar_Water_Heater_Controller |
