Description: Composed of intelligent DC voltmeter and DC relay control module,to realize accurate measurement of DC voltage. Set the upper and lower limits of the voltage, various delays, timing, and timing loops or combination of multiple modes,which realize simple and implementation of multiple system controls. Product design in strict accordance with national standards and electrical safety rules. Three high-brightness LED digital tube display; Card slot installation. Widely used in battery charge and discharge control, automotive battery control, electric vehicle power supply control, DC motor control, photovoltaic power supply system and over-voltage undervoltage protection. Specification: Material: Electronic Components Overall Size: 79x43x27mm/3.11x1.69x1.06inch Hole Size: 71.3x39.1mm/2.81x1.54inch Working Voltage: DC 10-15V (12V Relay Module) DC 20-30V (24V Relay Module) DC 40-60V (48V Relay Module) Timing Range: 0-99.9s,0-999s,0-999min (Optional) Standby Current: 15mA/12V Relay: 10mA/12V (Disconnected); 45mA/12V ( ) Working Temperature: -40~85℃ Size Chart: Function Description: F1: Automatic charge and discharge and voltage hysteresis control F2: Voltage overrun mode (overvoltage and undervoltage protection) 3: Battery automatic discharge control timing F4: Timing (delay) control F5: Manual control Note: 1. All button operations are divided into long presses and short presses. Long Presses: Press the button for about 3s to release. Short Presses: Press the button for 1s to release. 2.SET: Setting button. U/D: Operation button. Package Includes: 1 Piece Digital Relay Timer Module(2 Pack) Note: Color maybe slightly different due to different monitor. The above size is measured by hand, please allow slightly difference. Thanks !