Switch Indicator Module

Maretron SIM100-01 Switch Indicator Module

A vessel-wide safety and security monitor that puts the status of every switch closure device on your NMEA 2000 network — smoke, CO, bilge, door, hatch, valve, motion — visible on any compatible display anywhere on the boat.

Why It's Worth It
A bilge float switch that trips silently in an inaccessible compartment while you're asleep is useless. The SIM100 changes that: it continuously monitors up to eight switch closure devices and broadcasts their status over the NMEA 2000 network so any compatible display or N2KView software can alert the crew instantly. More importantly, the SIM100 can detect whether a monitored sensor has lost power or had its wiring disconnected — whether from corrosion, tampering, or failure — not just whether it's triggered. A sensor that's been silently dead for months but still shows "normal" is arguably more dangerous than one that's alarming. The SIM100 closes that gap.

Why It Matters for Installation
Note the IP64 ingress rating — lower than the IP67 of most Maretron products. Mount in a dry or only lightly damp location, away from engines or engine rooms where temperatures exceed 131°F (55°C). Orientation doesn't matter — horizontal, vertical, or upside down all work.

Use
Monitors switch closure devices including heat, smoke, carbon monoxide, and explosive vapor detectors; motion, vibration, glass break, door, hatch, and porthole magnetic switches; valve open/closed indicators; and high-water bilge switches. Compatible with Maretron-supplied sensors and most third-party switch closure devices with or without end-of-line resistors. Output displays on Maretron DSM250, DSM410, or N2KView software.