The 200 series control panels include models with an integrated monitor – same number of circuits, different level of monitoring. There are four levels to choose from, and the difference between them is greater than the display size suggests.
Why the monitor belongs in the panel
An integrated monitor saves a second cutout, a second installation location, and the wiring to it. For a panel that is already in a central location, this is the natural place for the display.
However, the decision for a certain level is less reversible than with a separate device: it is part of the panel. A change means replacing the panel – not just the display device. Therefore, it is worth thinking one step further than the current expansion level requires.
Level 1: the TCS tank monitor
The simplest level. A 2.4-inch TFT touchscreen shows the fill levels of up to three tanks and two battery voltages. This provides solid basic monitoring: you can see how full the tanks are and whether the battery voltage is correct.
What this level cannot do is just as important: a shunt cannot be connected here. Therefore, there is no current measurement and thus no state of charge – only voltage. A flow sensor is also not compatible, and this level is not P-Bus expandable.
It is the right choice if the question is indeed "how full are my tanks" and the battery is a secondary concern.
Level 2: the BTM 2
The next level provides more detailed battery data and an NMEA 2000 interface. This makes battery and tank values available on a chartplotter – a suitable adapter cable is available for connection to the network.
This level is the point where a display becomes a measurement: battery data now comes with a depth that allows statements about the condition of the bank, not just the instantaneous voltage.
Level 3: the PSM 3 system monitor
With the PSM 3, the full P-Bus system is integrated into the panel. The fundamental difference from the previous two levels is that it is no longer about more displays, but about an expandable network.
Shunts for battery monitoring, tank interfaces, temperature interfaces, relay modules for switching and dimming consumers, main switch interfaces, and inverters can be connected via the corresponding bridges. The monitor only shows the menus for which data is actually available.
Level 4: the PSL
The PSL offers the same P-Bus connection as the PSM 3, but with a 5-inch display featuring freely customizable arrangement of display elements. The advantage lies in usability: more information visible simultaneously, arranged according to personal priority instead of a fixed layout.
Functionally, the difference from the PSM 3 is minor; it lies in the screen real estate and ergonomics.
NoteThe crucial leap is between level 2 and level 3. Up to that point, it's about displays; from there, it's about an expandable system. Anyone who later wants to integrate shunts, solar, or other components should cross this threshold – regardless of display size.
Three deciding questions
- Should the state of charge be displayed? This requires a shunt – and therefore at least the third level.
- Should the system grow? Solar, additional tanks, switched consumers – all of this requires the P-Bus level.
- Should the data go to the plotter? Directly from the second level, or via the CBN bridge on the P-Bus level.
Typical mistakes when choosing
- Expecting state of charge from the entry-level. Without a shunt, there's no current measurement, only voltage.
- Deciding based on display size. The real threshold is P-Bus capability, not inches.
- Planning a flow sensor for the entry-level. It's not compatible there.
- Considering only the current expansion level. A later change means replacing the entire panel.
- Confusing expandability with display variety. More values on the display doesn't mean more can be connected later.
