With four ARM cores, a 1.2GHz clock and 1Gbyte of ram, it offers a considerable processing upgrade over the firm’s earlier Revolution Pi (one core, 700MHz, 500Mbyte).

The additional internal power consumption that goes along with the ~10x increase in processing throughput compared with the first version meant a considerable thermal upgrade inside the enclosure to avoid adding a fan.

The resulting fan-less design cools by convection through vent holes and all four cores can run at full speed at ambient temperatures under 20°C. Above this, the Broadcom BCM2837 processing chip has automatic clock throttling.

Tested ambient temperature figures with 100% processing are:

20°C 4 cores 1.2GHz

25°C 3 cores 1.2GHz, 1 core 1.1GHz

40°C 4 cores 1GHz (or at least 1 core 1.2GHz)

50°C 4 cores averaging 700MHz (or at least 1 core 1.2GHz)

65°C either 4 or 1 core in 400MHz ’emergency mode’ (300MHz for longer)

It is an upgrade to n the market: Our first and newest member of the Revolution Pi family which is equipped with a Compute Module 3.

Power needs to be fed in at a nominal 24V, (20.4 to 28.8V to meet En 61131-2 10ms voltage drop, down to 11V for normal continuous operation and 10.7V if 2 x 500mA USB out is not needed). Provided the functional earth connection is made, “lightening strikes or adjacent welding units were simulated in a certified test laboratory and could not affect the device”, said the firm.

There are two conventional USB sockets on the front, for USB sticks, for example, and a micro-USB socket to connect a host system (eg a PC) and switches the system to the passive memory card mode. “In this way, a PC can access an installed eMMC flash memory and store software there, for example,” said Kunbus.

LAN connection is via an RJ45 Ethernet socket or by adding a WLAN USB dongle.

A micro-HDMI socket allows a monitor with sound to be connected so, according to the firm “a fully equipped PC is available together with a mouse and keyboard.”

Kunbus also makes matching DIN rail I/O modules for it’s RevPis, and an DIN rail (45mm wide) wireless IoT gateway based around a Raspberry Pi Compute Module 3.

The gateway, called RevPi Connect, can use has a specially modified Raspbian version with a real time patch. “Common IIoT protocols like MQTT and OPC UA are supported to transfer machine data directly to the Cloud,” said Kunbus, “Individual applications can be programmed via, amongst other things, Node-RED, Python or directly in C.”

RS Components has published an industrial application example centred on a RevPi Core 3 and RevPi DIO (digital IO module).