Measuring & Control — SMSCOM

SMSCOM solves the expansion problem differently from most controllers. Instead of buying a heavier box when you add a second room, you hang a slave unit beside it and drive it from the same master. That makes this brand most interesting to anyone expecting the setup to grow.

Master and slave

The Twincontroller comes as MK2 in 4.5 and 7 A and as PRO in the same sizes, with a PRO Slave MK2 7 A to pair with it. The switch boxes work the same way: the SPC in 8 and 16 A with an SPC Slave 16 A alongside. You then run two rooms or two groups from one point without keeping two sets of settings in step.

Sensors are separate, and that is deliberate

The NTC sensor and the light sensor for the Twincontroller PRO are bought separately. That looks inconvenient and is the reason you can hang the sensor where you need it rather than where the box happens to be. A temperature sensor reading beside the door tells you something different from one at canopy height under the lamp, and that difference is exactly what you are controlling on.

How this brand compares with the other controllers here

We stock several controller brands in this category. The choice is less about features, which overlap, than about what your system looks like in two years. One room that stays one room is served fine by a single box. If you expect to expand, or already run separated groups, SMSCOM's master and slave layout is built for it.

Frequently asked questions

Can I add a slave later?
That is the idea. Do check which slave belongs to which master, because MK2 and PRO are not freely interchangeable.

How many amps do I need?
Add up what hangs off it and allow margin. The rating is in the model name.

Do I need the sensors?
For temperature control, yes. Without a sensor the controller can only switch on time rather than on what the room is doing.