Power Step PSA-D11R-FL, Manual

FOLDING STAIRWAY

Caterpillar D11R Dozer

Pg29

PSA-D11R-F/L

210610

10)

Once the ladder has been raised and reached its top proximity switch the hydraulic 
motor will run for an additional three seconds to ensure it is fully stowed.

11)

This system also features optional locks which are for any electric or electric over 
hydraulic function which may need to be locked out to prevent damage to the 
ladder system (i.e.) swing and/or travel on excavators. This can be used with or 
without the park brake system. The system has N.O. and N.C. options and can be 
used easily integrated into any system to inhibit swing/travel until the ladder is fully 
raised.

12)

This system also features an optional door proximity switch; this switch if used, is 
designed to prevent the ladder from being raised if the cab door is ajar. It is a N.O. 
proximity thus; if this option is not used the bypass plug must be fitted. If the cab 
door is accidentally opened whilst the ladder is being raised, it will stop and then 
continue once the cab door is closed again.

13)

Motion delay can be inhibited by removing Diode 6 to inhibit the delay in the 
upward direction. Diode 7 can be removed to inhibit the delay in the downward 
direction.

14)

Mounted in the optional Boarding Lamp Switch Housing is an additional lower 
button, this is to enable the operator to operate the down function from an 
alternative position, one or more of these stations can be used. 

15)

Should the park brake system not be used, a by-pass plug must be fitted otherwise 
the alarm in the cab will not operate. In this condition the alarm in the cab will 
operate whenever the step is not fully home (up). We recommend during shutdowns
or extended periods of time when the machine is to be worked on with the ladder 
down, the system be isolated.

16)

The system must have both the up (top) and down (bottom) Proximity Switches 
used.

17)

The timers are all set for different functions and must not be interchanged.

18)

The circuit breakers used are called alternative function circuit breakers which 
mean if they "trip out" on over current the supply must be cut and then re-applied to
re-set them - turn the system off and then back on.

19)

The kit is supplied with a 120 amp Circuit Breaker/Bracket Assembly. We 
recommend taking the power supply from the isolated side of the battery isolator (If 
positive is isolated) or the battery itself. The circuit breaker should be mounted as 
close to the battery positive terminal as possible, using the cable lug covers for all 
exposed connections and a minimum of 3AWG/3B+S battery cable. Larger cable is 
recommended on a long cable run. Suitable cable protection and cable restraints 
should be used in accordance with normal good practice.

Access System Electrical Overview (cont.)