Sequent Microsystems Launches Crowdfunder for Its Stackable, Four-Relay Raspberry Pi Add-On
Offering up to 32 relays per Raspberry Pi — or 64 in its 8-relay variant — the new board looks to make home and industrial automation easy.
Sequent Microsystems has launched a crowdfunding campaign for a four-relay add-on for the Raspberry Pi, but it comes with a trick up its sleeve: Multiple boards can be stacked, allowing a single Raspberry Pi to drive 32 relays.
"This card adds four line-switching relays to Raspberry Pi. It can be used to control loads of up to 10A and 250V. You can control directly all your lights and appliances," explains Sequent's Mihai Beffa of the design. "Pluggable connectors accept 18 to 22 AWG wires and simplify the installation, specially if you are planning to use more than one card."
The four-relay stackable design follows on from an eight-relay variant, also stackable, launched by the company back in 2018. As with its predecessor, the four-relay board comes with command-line and Python control software as well as a sample application for controlling the relays through a browser in JavaScript.
Interestingly, it's also possible to mix and match the boards: Original-model eight-relay boards and the new four-relay boards could, theoretically, be stacked up to 16 units high for a total of 96 relays on a single Raspberry Pi — though Beffa warns that "this creates mechanical problems, and I do not know if I2C will accept such a long physical line." New-model eight- and four-relay boards, meanwhile, can be mixed in any order up to eight combined units high.
The four-relay boards are on Kickstarter now, with pricing starting at $20 per unit and delivery expected in July; the eight-relay variant, meanwhile, is for sale on the Sequent Microsystems website priced at $30 with immediate availability.