**Details** These relays are rated for 1A/30V. To activate a relay, set the corresponding control line LOW. When left unconnected, control lines default to HIGH (and, hence, relays are off). Combine this Tibbit with terminal block devices -- #20 (nine terminal blocks) or #21 (four terminal blocks). **LEDs** There are two red LEDs which are connected to two relay control lines. LEDs light up for the LOW state of control lines (i.e. when relays are activated).