Knowledge Base › Wiring guide: Mighty Mule MM371W and MM372W

Wiring guide: Mighty Mule MM371W and MM372W

This guide shows where each wire from the Nimbio terminal strip lands on the MM371W/MM372W control board. Gate Status: wired via the AUX relay, which reports whether the gate is operating or at rest, not whether it is open or closed.

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Before you start

Power the operator down at its supply before touching any terminal.
The Nimbio terminal strip has eight terminals: PWR+, PWR-, Sense 2, SC, Sense 1, NC, C and NO. This guide wires Sense 1 and SC; Sense 2 is not used (see “Connections”).
Power: PWR+ and PWR- land on AUX V+ and AUX V-, which draw from the operator’s own battery. On a solar-powered gate, use a separate supply instead — see Cautions. The Nimbio accepts 6.5 to 24 V AC or DC.
You need a small screwdriver for the terminal screws.

Nimbio terminal strip (left) to the MM371W/MM372W control board (right). Wire tags name the destination terminal. On a phone, scroll the diagram sideways or pinch to zoom; the Connections list below has every wire.

Connections

Nimbio terminal	Operator terminal	Number	Board	Note
PWR+	AUX V+	—	MM371W/MM372W control board	Draws from the operator’s own battery — see Cautions for solar sites.
PWR-	AUX V-	—	MM371W/MM372W control board
Sense 2	Not used	—	—	Not used. The AUX relay is a single contact reporting operation vs. rest; a second sense line on it would only mirror Sense 1.
SC	AUX C	—	MM371W/MM372W control board	Sense common; the other side of the AUX relay from Sense 1.
Sense 1	AUX NO	—	MM371W/MM372W control board	AUX relay; active only while the gate is operating.
NC	Not used	—	—	Not used: the operator input is wired to NO and C.
C	COM	—	MM371W/MM372W control board
NO	EXIT	—	MM371W/MM372W control board

PWR+

Operator terminal: AUX V+Number: —Board: MM371W/MM372W control boardNote: Draws from the operator’s own battery — see Cautions for solar sites.

PWR-

Operator terminal: AUX V-Number: —Board: MM371W/MM372W control boardNote:

Sense 2

Operator terminal: Not usedNumber: —Board: —Note: Not used. The AUX relay is a single contact reporting operation vs. rest; a second sense line on it would only mirror Sense 1.

Operator terminal: AUX CNumber: —Board: MM371W/MM372W control boardNote: Sense common; the other side of the AUX relay from Sense 1.

Sense 1

Operator terminal: AUX NONumber: —Board: MM371W/MM372W control boardNote: AUX relay; active only while the gate is operating.

Operator terminal: Not usedNumber: —Board: —Note: Not used: the operator input is wired to NO and C.

Operator terminal: COMNumber: —Board: MM371W/MM372W control boardNote:

Operator terminal: EXITNumber: —Board: MM371W/MM372W control boardNote:

When the wiring is done, restore power at the supply. A Nimbio support team member then calls to test the gate before you close the panel.

Settings on the operator

No operator setting is changed by this guide.

Gate Status

Gate Status: wired. Sense 1 and SC connect across the AUX relay, which activates during gate operation and stays activated for the duration of the operation. Sense 1 reports whether the gate is moving or at rest, and Nimbio maps those two states to the labels shown in the app. Sense-line polarity does not depend on the wiring. Nimbio maps each sense line’s triggered and untriggered state to an Open or Closed label after installation. If Gate Status shows the opposite of the physical gate, contact Nimbio support to have the labels switched; no rewiring is needed.

No suitable output on your operator? A magnetic gate switch can report the gate’s position instead: wire its two leads to Sense 1 and SC for fully closed, or to Sense 2 and SC for fully open. The switch must be a dry contact that puts out no power of its own; if yours puts out power, add a relay that turns it into a dry contact.

Frequently asked questions

Does the MM371W/MM372W need an expansion board for Gate Status? +

No. Sense 1 and SC land on the AUX relay on the main control board.

Which Nimbio terminals open the gate on the MM371W/MM372W? +

NO and C, wired to EXIT and COM. The Nimbio relay closes NO to C, which the operator reads as an open command.

Does Gate Status report open and closed on the MM371W/MM372W? +

No. The AUX relay only reports whether the gate is operating or at rest, not which position it stopped in.

Can I power the Nimbio from AUX V+/V- on a solar-powered gate? +

It is not recommended. The manual caps continuous solar-safe draw at 20 mA and the Nimbio draws more than that; give the Nimbio a separate supply on a solar-only site.