The Difference Between Mechanical and Electronic Blind Motor Limits
If you’ve ever specified roller blinds or spoken to a manufacturer like Umbra before, you’ve probably heard the phrases ‘MM’ and ‘ME’ motors being used.
Do you know what these terms mean? Let me explain.
Put simply, they are used to describe how your limits are set on your motor. Specifically, on Vestamatic motors. Vestamatic coined this name for their tubular motors originally but is sometimes by those in the industry to describe any motor with mechanical or electronic limits.
‘Limits’ are the pre-set positions where your blind stops. There is always a top limit, where the blind stops when it’s fully open, and a bottom limit where it closes. Sometimes there are intermediate, or middle, limits too depending on the motor type.
An MM motor is one with mechanical limits. Mechanical limits are set and stored physically via mechanical components inside the motor. This is done by turning an ‘adjusting screw’ or buttons on the motorhead to set the limit position.
An ME motor is one with electronic limits. Electronic limits are stored within the motor’s electronics. This means the limits can be set using a setting tool, which is plugged into the motor. This gives you a bit more flexibility because it means you don’t have to be as close to the motorhead.
When we’re talking about MM and ME motors, chances are that we’re talking about a hardwired, switch-controlled motor i.e., the motor is directly wired into a control switch or BMS (Building Management system). However, radio motors are also technically ME motors. Radio motors have electronic limits. These can be set from a handheld remote or in some cases a setting tool, which simplifies the process. It’s much easier to use the setting tool as mistakes can be easily corrected with the reset button. Using a remote or switch makes it trickier to fix these mistakes, which can prolong the installation process.
Mechanical Limits & Rooflight Blinds
One issue we see crop up often is when somebody wants to use an MM motor on a rooflight blind. The issue with this when your rooflight blind is in standard orientation (headboxes facing upwards) is that the motor is behind the fabric. This makes it virtually impossible to access the motor and set the limits.
If you did want to use a motor with mechanical limits on a rooflight, we’d suggest requesting reverse orientation with the headboxes facing downwards. This gives you access to the motor when the blind is fitted.
If your rooflight blind is in standard orientation, we would recommend radio motors or, at the least, a motor with electronic limits and a setting tool. It just makes life so much simpler for your fitter.
So which is better?
Well, it depends on what your main priority is. For a simpler installation, we would recommend choosing a motor with electronic limits. They are much easier to work with and will end up saving your fitter time on site. The other key difference is that motors with electronic limits can be wired in parallel (or daisy-chained) so multiple motos can controlled from one switch without a relay. With mechanical limits you can only have one motor per switch without a relay. To control multiple motors will always require a relay.
However, if your project has a strict budget, or where you only need one or two motors, you could use a motor with mechanical limits. These tend to be cheaper than electronic limits, so it could end up saving you money.
Do you need help choosing a motor for your next project? Get in touch.
Or visit our Motor Setup Guide page. It has tons of free videos and downloadable PDF’s to help you programme motors from Vestamatic, Somfy, Nice and more!