Understanding 5V Eight-Channel Relay Module Single-channel relay module, dual-channel relay module, four-channel relay module. Relay maximum contact voltage – 250VAC, 30VDC.Current when relay is active - ~70mA (single), ~600mA (all eight).The following are the major components present on the eight-channel relay module, which will be described in detail later in the article.ĥV relay, terminal blocks, male headers, transistors, optocouplers, diodes, and LEDs.Įight-Channel Relay Module Specifications Each relay on the board has the same circuit, and the input ground is common to all eight channels.Ĭomponents Present on an Eight-Channel Relay Module The eight-channel relay module contains eight 5V relays and the associated switching and isolating components, which makes interfacing with a microcontroller or sensor easy with minimum components and connections.