MDV battery switch module (010010029) — Overview

This firmware makes the module the boat's main battery switch: the one that connects the service bank to everything else, and that decides when the boat is on and when it is off.

It does three things at once.

It operates the switch. The main switch is a remotely operated one, opened and closed by a pulse on one of two coils. The module drives those coils, watches the switch's own feedback contact, and stops as soon as the switch has really moved. From a MUXEN screen, from a button wired anywhere on the boat, or from a logic equation, the boat is switched on and off here.

It powers the MUXEN bus. While the main switch is closed, the module feeds the MUXEN bus and an auxiliary output from the battery, and measures the current it is injecting. When the switch opens it does not cut that power immediately: it holds it for ten minutes, so the Brain, the screens and every device on the bus have time to shut down cleanly. Then the module goes quiet and the boat is genuinely off.

It reads the battery. A Hella IBS sensor on the battery post is polled continuously over LIN, and published on the MUXEN bus as an ordinary MUXEN battery — voltage, current, temperature, state of charge. No other equipment on the boat needs to know where the figures came from.

It also announces the two moments that matter to the rest of the boat: the instant the switch closes and the instant it opens. Both are flagged in the module's own frame, and other devices use them to start up and to shut down in order.

What it is not

• It is not a battery monitor for the whole boat. One module, one sensor, one battery.
• It is not a BMS and it is not a charger. It reports what the sensor measures and it asks for charge or not; it regulates nothing.
• It does not measure the boat's consumption. The current it publishes is what it injects onto the bus and the auxiliary output, not what the bank delivers.
• It is not a gateway. There is no second CAN bus and nothing to translate — the only other wire is the LIN pair to the battery sensor.

It commands a main battery switch

Read that again before wiring anything. Closing this switch energises the boat; opening it de-energises it, including the MUXEN bus itself. The module will do that on a command arriving over the bus, and it will do it on a rising edge of the equation you write into it. Decide what is allowed to switch the boat off before you configure it.

Identity

Product ID	010010029
Hardware	can-mdv v2 (990010058)
Software ID	990050019
Version	6.2
Image	010010029-V2-app_mdv-firmware.srec

Limits

Main switches driven	1
Battery sensors read	1
MUXEN instance numbers	0 – 62

Read next

• What you need — what to order and how to wire it
• Commissioning — commissioning
• Common mistakes — MDV battery switch module — what usually goes wrong
• Reference — MDV battery switch module — parameters, devices, timings
• can-mdv — what is true of every can-mdv box