RK4 is a unique relay module intended for use with various Ontrol controllers or any BMS system to enable on/off switching of loads. It provides 4 independently switchable relays. For each relay, both normally-open and normally-closed contacts are available for wiring. LEDs indicate status of the relays and supply voltage.
RK4 has two modes of operation.
- Analog Control : A 0-10 V input is provided for controlling each relay independently. In this mode, the RK4 is a general-purpose analog-to digital converter that can be used with any BMS controller. See specifications for switching voltages.
- Ribbon-cable connection : When connected to a compatible Ontrol controller via the ribbon cable connection, the relays are directly controlled by the attached controller. In this case, analog input terminals are not used.
Ribbon cable connectors are on the bottom of the module, allowing the cable to lie flat in the DIN rail. Two connectors are provided to allow daisy-chain connection of multiple RK4 modules:
P-ION : max 2 relay modules for up to 8 relay outputs
R/MIO : max 1 relay modules for up to 4 relay outputs
R/TIO : max 2 relay modules for up to 8 relay outputs
M/TIO : max 2 relay modules for up to 8 relay outputs