M3 vibrator motor : the compact ATEX series for zones 21 and 22

The M3 series occupies a precise place in the Italvibras catalogue : that of the compact vibrator certified for combustible dust, in zones 21 and 22. Six references, from 0.30 to 2.94 kN, all on the same frame size 00, from 4.3 to 6.3 kg.

Two features set it apart from the rest of the range : the terminal box is placed under the machine, on the same side as the base, and that base is multi-hole, which makes it possible to reuse existing hole centres without re-drilling.

The six references are also available in single-phase version 100-130 V 60 Hz or 200-240 V 50 Hz.

The six references compared

Overall dimensions from the Italvibras catalogue (A × C × B).

Choosing within the M3 series

All references share the same frame, the same certification and the same transverse dimensions. The choice therefore comes down to two questions, and to a third that sometimes leads out of the series.

2 or 4 poles : releasing or moving

The four M3 run at 3,000 rpm : many short impulses, ideal for breaking the adhesion of a dry product on a wall, a sleeve or a screen. The two M15 run at 1,500 rpm and produce a wider movement at lower force : that is what is needed to move a product forward without churning it, or to handle a wet or sticky material that high frequency would merely compact.

Force, and a special case at 60 Hz

In 2 poles, the scale runs from 0.635 to 2.94 kN, almost a factor of five at nearly identical size — only the length goes from 197 to 235 mm. One point deserves attention : on the M3/305-S02, the catalogue gives a lower static moment at 60 Hz than at 50 Hz, so that the force there drops to 2.87 kN instead of rising. On a 60 Hz supply, the M3/205 and the M3/305 therefore deliver the same.

When the M3 series is not the right one

• If the force required exceeds 2,94 kN, you must move to the conventional foot-mounted series.
• If the atmosphere is gaseous, the M3 does not suit : its II 2 D certification covers dust only. You must then look at the flameproof or increased-safety series.
• If only zone 22 is involved and the force remains low, the MICRO series is more compact and less expensive.
• If you need certification for gas and dust in this compact size, the M3-E series is the one to look at.

Two mounting details

The terminal box under the machine is an advantage in dusty environments, but it requires you to provide access from below when connecting. And the thermal protection is not fitted as standard : the 130 °C PTC thermistor is available on request, and becomes necessary if you plan to drive the unit with an inverter.

Data from the Italvibras general catalogue 2019, pages 50 to 53. Audimat Automation, official Italvibras distributor.