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WARNING
Improper microswitch adjustment may re- sult in serious bodily injury and/or property damage.
Microswitches: Three micro- switches (limit switches) are incorporated in the RA300 Ramp electrical system. "Y" ramp mod- els microswitches are: Drift-In,Drift-Out and Counter. The "YP" ramp model also has three micro- switches: Drift-In,Drift-Out and
Power Down Activation. Details and photos of the microswitches DUHSURYLGHGEHORZ$GMXVW microswitch(es) as detailed (if necessary only).
Stowed Position: When the ramp is in the stowed posi- tion, the Drift-Out and Counter microswitches are deactivated (common and normally closed terminals have continuity). In contrast, the Drift-In microswitch is activated.
Deploy Sequence: When the ramp is in the stowed position, the Drift-Out microswitch is deacti- vated. Current is allowed to pass from the vehicle Deploy Relay, which directs current to the Bidi- rectional Pump motor in direction A (hydraulically drives cylinders to deploy ramp).
When the ramp’s platform reach- es the Drift-In limit (approx. 45° above ground level), the micro- switch is activated (common and normally open terminals have continuity), and the current to the Deploy Relay is interrupted thus stopping the current to the pump motor. The platform then “drifts”
downward to ground level, during which, at some position, the Drift- Out microswitch is activated. The Drift-In microswitch is deactivated during the deploy movement of the platform. Note, however, that neither of the other 2 micro- switches have any bearing on the deploy sequence.
Deployed Position: When the ramp is in the deployed posi- tion, the Drift-Out and Counter microswitches are activated. In contrast, the Drift-In microswitch is deactivated.
Stow Sequence: When the ramp is in the deployed posi- tion, the Drift-In microswitch is deactivated, allowing current to pass from the vehicle Stow switch circuit and energize the ramp Stow Relay, which directs current to the Bidirectional Pump motor in direction B (hydraulically drives cylinder to stow ramp).
When the ramp’s platform reach- es the Drift-Out limit (approx. 45° above ground level) and deacti- vates the microswitch, the current to the Stow Relay will be inter- rupted.
"Y" Models Only: When the ramp’s platform reaches the Drift-In limit (approx. 15° above YHKLFOHÁRRUOHYHOWKHPLFUR- switch is activated and the current to the Stow Relay is interrupted thus stopping the current to the pump motor. The platform then “drifts” downward to the vehicle ÁRRU7KH'ULIW2XWPLFURVZLWFKLV also deactivated during the stow movement of the platform