Manual Motor Starter

[warraich]

Hello everyone,

I was reviewing a wiring diagram of the Eaton MST manual motor starter for single-phase motors and wanted to get some input from the forum members to ensure I’m interpreting the diagram correctly.

As per the wiring diagram (attached for reference):

• In HAND mode, the toggle is closed. Does this imply that the thermostat is bypassed? If so, why?
• In AUTO mode, does this mean the thermostat is not bypassed?

Thank you in advance for sharing your expertise!

 

[MTW]

Can you share where that drawing came from?

 

[warraich]

Can you share where that drawing came from?

yes, here is the link:

https://www.eaton.com/content/dam/eaton/products/industrialcontrols-drives-automation-sensors/manual-motor-starters-/enclosed-manual-motor-starter-with-run-light-and-hoa-pa038001en.pdf

 

[retirede]

Your understanding is correct. Follow the circuit.

 

[hbiss]

In HAND mode, the toggle is closed. Does this imply that the thermostat is bypassed? If so, why?

I believe that that application is just to illustrate a possible use for the starter/control station and how it functions.

-Hal

 

[MTW]

In the hand mode, it's a manual on, just like the manual starter switch contacts. It Would allow you to put the Hand /Auto switch elsewhere as stated in the description. to override the thermostat.

In the Auto mode it cycles on the thermostat.

 

[warraich]

thanks everyone for your input

 

[Jraef]

I believe that that application is just to illustrate a possible use for the starter/control station and how it functions.

-Hal

I agree, it’s just illustrative of options, because otherwise it doesn’t really work differently in hand or auto. It’s only On when the switch is closed, nothing works when it is open, regardless of the thermostat.