140
Service Manual – SC500
34 - Scrub System, Disc
Brush Deck Actuator System
The brush deck actuator of SC500 is a new generation actuator developed by SIR and ITALSEA and it is
controlled directly by the Main machine controller (EB1) without electromechanical limit switches ITALSEA
patented the system to control the actuator Basically the system uses deeply measurements of the current
flow in the actuator to know its position in real time.
The actuator is mechanically proof of the end of stroke because of it reaches the end of stroke with limited
voltage applied and so with a limited speed and force
The actuator moves and stops in 3 defined positions:
1 RETRACTED: fully retracted end of stroke (deck lifted)
2
WORK: intermediate position (deck on the floor, normal work condition)
3
EXTRAPRESSURE: fully extended end of stroke (deck on the floor with extrapressure given pressing
the actuator integrated spring)
The actuator is powered at 50% PWM (about 12Vdc) near the end of strokes or during the machine switch-on
reset feature, otherwise at 100% PWM (24Vdc)
The machine switch-on reset feature moves the actuator from the position where it was the last time the
machine was switched off to the RETRACTED position
The quotes of the actuator strokes, with a tolerance of ±2mm are: stroke RETRACTED-WORK = 3 3 in (85
mm), stroke RETRACTED-EXTRAPRESSURE (end to end) = 4 7 in (120 mm)
There are time out limits and amperometric limits related to the different phases of the movement as follow:
Movement from: To:
PWM
AMP limit
Alarm if AMP limit
reached
Timeout
Extrapressure
Work
100% (=24Vdc)
4A per
Time>1sec.
Yes
7.5 sec.
Work
Retracted –
0.4 in (10 mm)
100%(=24Vdc)
4A per
Time>1sec.
Yes
15 sec.
Retracted –
0.4 in (10 mm)
Retracted
50%(=12Vdc)
2A per
Time>1sec.
Not (Main machine
controller assumes the
actuator reaches the
end of stroke)
Reset (during machine switch on) 50%(=12Vdc)
2A per
Time>1sec.
Not (Main machine
controller assumes the
actuator reaches the
end of stroke)
25 sec.