Technical Documentation

Product Identification

• Brand: SINOTIMER
• Model: OBS-40
• Type: AC surge arrester (SPD)
• Configuration: 2 poles (L + N)
• Protection Class: Type 2 (T2)
• Rated AC Voltage (Uc): 275 V AC
• Nominal Discharge Current (In): 20 kA (8/20 µs)
• Maximum Discharge Current (Imax): 40 kA (8/20 µs)
• Protection Level (Up): 1.8 kV
• Standards: IEC 61643-1, GB/T18802.1
• Applications: Protection of single-phase AC electrical installations

General Description

The SINOTIMER OBS-40 surge protection device is a protective device designed for alternating current electrical installations, used to reduce transient overvoltages caused by indirect lightning strikes or network switching. The device protects connected equipment by interrupting pulse overvoltages to the grounding system.

The OBS-40 model is designed for single-phase networks with L+N configuration, suitable for use in residential, commercial, or industrial electrical panels.

Visual Indicators and Operating Status

• The device features a visual status indicator visible on the front of each unit.
• The green color indicates normal operation and active protection.
• The color change indicates internal component degradation and the need for unit replacement.

Construction and Connection Instructions

The arrester consists of two SPD modules mounted in a modular casing. The upper terminals are clearly marked L (phase) and N (neutral). The lower terminal is for connection to ground (PE). Connections are made via screw terminals, ensuring a stable and secure contact.

Protection Operation

The SINOTIMER OBS-40 Type 2 arrester limits transient overvoltages on the AC network and reduces them to a safe level for the protected equipment, with a protection level Up of 1.8 kV. It is designed to withstand repeated surge events within the specified nominal and maximum current limits.

Electrical Main Parameters

• Maximum continuous AC voltage (Uc): 275 V AC
• Nominal discharge current (In): 20 kA (8/20 µs)
• Maximum discharge current (Imax): 40 kA (8/20 µs)
• Protection level (Up): 1.8 kV
• Test pulse type: 8/20 µs

Installation

• Typical installation on a 35 mm DIN rail
• Suitable for single-phase AC electrical panels
• Immediate and as short as possible connection to the grounding rod
• It is recommended to install as close as possible to the point of entry of the installation or to the protected equipment

Important Notes

• The device does not provide protection against overvoltages or short circuits and does not replace fuses or circuit breakers.
• Proper grounding connection is essential for effective protection operation.
• If the visual indicator signals a fault, the unit must be replaced to maintain the protection level.