Hill-Rom Advanta P1600, Service Manual

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Theory of Operation
Chapter 3: Theory of Operation
Page 3 - 14 Advanta™ Bed Service Manual (man168ra)
board assemblies to reduce errors in servicing. The siderail cable, part number
63600, connects the siderail interface P.C. board and the logic control P.C.
board. This cable, with its multi-colored wires, is an exception to the single
color rule. Due to its round jacket construction, the cable must be constructed
of multiple colors.
Power is applied to the logic control P.C. board on connector P11 via a power
noise filter and a molded plug power cord arrangement. The AC input is
applied first to the logic control P.C. board via power cord, part number 64017,
and then connected to the power supply module via a two-conductor cable, part
number 63715, on connector P9.
Capacitors that are used in the split-phase motor network are attached to the
logic control P.C. board on connector P7 via a 9-position cable assembly, part
number 64027. This allows the capacitors to be mounted remotely from the
motors in a location on the retractable frame under the dust cover. This allows
for ease of service on the motors and the capacitors.
The limit system inputs to the logic control P.C. board on connectors P19 and
P2 are developed by the Hall effect/magnet sensors mounted on the
intermediate frame of the bed on separate assemblies. There are a total of 14
sensors on four drives. There are two intermediate hilow sensors mounted on
each of the bed up-and-down drives that allow for reverse trendelenburg and
chair positioning above the low-low limit of the bed. This prevents interference
between the bed members and associated bed parts. Each of the four drives has
an upper and lower limit present to stop drive operation at the extremes. There
is an additional contour limit on the head and knee drive to stop articulation at
the contour limit points. The flip-flop cam on the Hilow drives is a
deterministic limit to inform the logic that the bed frame is below or above the
intermediate low limit for Reverse Trendelenburg, Trendelenburg, and chair
positions.
There is an interconnection scheme for the limit system. The logic control P.C.
board connects to a connector P.C. board via connector P19. The cable
interface is part number 63718. The connector P.C. board, part number 63208,
has three independent cables connected to it from each of the intermediate
frame- mounted limit systems. The head hilow drive is connected with cable
part number 6148701 and provides the limit signals for the head hilow drive
system. The foot hilow is connected with cable part number 6148903 and
provides the limit signals for the foot hilow drive system. The head drive
assembly and CPR switch assembly are connected via cable part number
6148801, and provides the CPR switch input and the head drive limit switch
signals.