A resistance sender and gauge are designed to work one-to-one — one sender, one gauge. As soon as you want a second gauge reading the same tank, or two senders feeding a single gauge, wiring them together directly throws the readings out. The Dual Station Converter sits in between and sorts the signals so everything reads true.
The short version
Both setups need a Dual Station Converter. It works with analogue gauges only — you can't mix an analogue gauge with a digital or NMEA 2000 gauge on it.
01One sender, two gauges
The classic case is a boat with two helm positions — a flybridge and a lower helm, say — where you want the same tank shown on a gauge at each station. You can't simply wire one sender to two gauges: the two gauges sit in parallel, which changes the resistance the circuit sees and makes both read incorrectly.
The Dual Station Converter takes the single sender input and drives two independent gauge outputs, so each gauge reads the tank correctly.
02Two senders, one gauge
Any time the fuel or water can move, a single sender only sees its own spot. On a boat that's pitching and rolling; on a vehicle it's fuel surging fore and aft under braking and acceleration in stop-start driving, or to one side when cornering. Shallow or awkwardly shaped tanks make it worse still. Fitting two senders and averaging them gives a far steadier, more accurate reading.
For the steadiest reading, fit the two senders at diagonally opposite corners of the tank — whichever way the liquid surges, one rises as the other falls, so the average holds true. The Dual Station Converter combines the two sender signals and feeds that average to a single gauge.
The part you need
Dual Station Converter
One box covers both jobs — two gauges from one sender, or two senders averaged onto one gauge. Analogue gauges only.
03Common questions
Can't I just wire one sender to two gauges directly?
No. Two gauges wired in parallel change the resistance the sender sees, so both read incorrectly — usually over-reading. The Dual Station Converter drives each gauge independently so both read true.
Will it work with a digital or NMEA 2000 gauge?
No — it's for analogue gauges only, and you can't mix an analogue gauge with a digital or NMEA 2000 one on it. To run a digital system, put the sender onto the network with an NMEA 2000 converter.
Why fit two senders on a RIB or small boat?
On a tank that moves or is shallow, the level at any one point undulates and isn't representative. Two senders at opposite ends, averaged, give a steadier and more accurate reading.
Where should I fit the two senders?
Diagonally opposite corners of the tank works best. Whichever way the liquid surges — fore and aft under braking or acceleration, or side to side when cornering or rolling — one sender rises as the other falls, so the average stays close to the true level.
Do the senders and gauges all need the same resistance?
Yes. Everything on the circuit must share the same resistance standard — see European vs American resistance.
Not sure what you've got, or planning a more involved setup? See how to identify a replacement Wema sender, or get in touch and we'll help you wire it up.