Credit to Kendall Alstatt TMHU
“What is the background on OPSS travel control and how does it work?”
The “Operator Presence Sensing System” or “OPSS” for short was introduced on all 7-Series sit down forklift products in the fall of 2005, in response to a new safety standard required by the “American Society of Mechanical Engineers” (ITSDF ASME B56.1). The new standard states, “Powered travel shall be possible only if the operator is in the normal operating position”; the standard also states: “Powered travel may not occur automatically when the operator returns to the normal operating position without additional operations”.
- The OPSS controller monitors the status of the seat switch to determine if the operator is correctly seated. If the seat switch status changes from “closed” to “open” for more than 2 seconds during powered travel; the OPSS controller will force the transmission into “neutral” and powered travel is interrupted. Any time the OPSS system is active, the OPSS lamp is illuminated on the operator’s display.
- After the operator returns to the seat and the seat switch status is “closed” for more than 1 second, the OPSS controller confirms that the directional control lever is in neutral and not in either the FWD or RWD direction, the OPSS controller will no longer interrupt powered travel. This is commonly known as a “Static Return to Off” (SRO) function. When powered travel is resumed the OPSS lamp turns off.
Toyota has taken an additional step with the OPSS system, for the safety of the operator and others working in the area of the forklift, the OPSS system also does not allow material handling operations to function when the operator is not sitting in the seat.