Operator Presence device (OPS)

Sears Craftsman speak Mowers conform to safety codes standardized for all American produced lawn tractors. The security switch in ~ the seat is only one component of the numerous interconnecting safety attributes of the contemporary riding mower. If the mechanism works properly, the owner must be seated because that the mower deck come operate. The tractor will continue running with the strength Take off or PTO disengaged if the parking brake is set before the operator leaves the seat.

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Switch Operation

The seat switch is composed of two electrical contacts typically separated by an air gap. A spring creates an open space between the two contacts. An installed between two plates, the switch"s spring compresses under the weight of the person sitting in the operator seat and completes an electric circuit. With the switch closed the tractor"s ignition system deserve to be switched on v the ignition key. If the operator stands, the spring pressures the space open and also interrupts the electrical ignition circuit.


Sears Craftsman riding Mowers conform to security codes standardized for all American manufactured lawn tractors. Placed between two plates, the switch"s spring compresses under the weight of the human being sitting in the operator seat and also completes an electric circuit.

Parking Brake Option

The safety and security circuit enables the speak mower engine to proceed running if the PTO is not engaged, the parking brake is set, and also the operator leaves the seat. Once the parking brake is set a 2nd switch in electrical parallel through the OPS closes. This bypasses the security switch under the seat. If the operator stands, the parking brake switch still completes the ignition circuit.


Power Take off Option

The mower blade turns only when the PTO engages. If the operator should leave the seat v the blade transforming and under power, injuries could result. The mower blade would even proceed spinning at complete power if the an equipment overturned. To avoid this form of accident, engaging the PTO deactivates a link in the initial circuit and completes a second circuit in series with the OPS switch.


The safety and security circuit allows the speak mower engine to continue running if the PTO is no engaged, the parking brake is set, and the operator pipeline the seat.

If the operator pipeline the seat with the PTO engaged, the ignition interrupts and also the maker stops. This often reasons problems for new owners who forget come disengage the PTO when turning off the ignition. Until the PTO is off, no mix of settings will restart the mower.

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Anti-Reverse

Lawn tractor mowers will not automatically mow in reverse gear. The seat move plays a failsafe role in this safety function as well. In reverse equipment the relay managing the PTO switches off and the tongue stops. Come override that the operator must set the ignition move to the manual override setting. Leaving the seat at any kind of time during this procedure switches off the mower.


If the operator leaves the seat v the PTO engaged, the ignition interrupts and the machine stops. Till the PTO is off, no combination of setups will restart the mower.






James Young began writing in 1969 together a army journalist combat correspondent in Vietnam. Young's articles have been released in "Tai Chi Magazine," "Seattle Post-Intelligencer," Sonar 4 ezine, "Stars & Stripes" and "Fine Woodworking." he has operated as a foundryman, woodturner, electronic devices technician, herb farmer and woodcarver. Young i graduated from north Seattle neighborhood College v an associate level in applied science and also electronic technology.