Hill-Rom CareAssist P1170, Service Manual

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Electrical System
Chapter 3: Theory of Operation
CareAssist™ Bed Service Manual (man330) Page 3 - 7
3
Battery Characteristics
Table 3-3. Battery Backup Characteristics
The batteries are a sealed lead acid and are connected in series on the main
board and protected by a 10 Amp fuse on the connection wires.
The battery type has no memory effect and can be charged regularly without
any particular constraints.
The capacity of the battery backup after full charging is at least three raise and
lower cycles for hilow, head section, knee section and foot section with the
maximum safe working load 400 lb (185 kg) on the bed.
Control Logic and Specific Functions
Combined activations of the motor provide the following functions:
• Dining Chair™ Position
• Automatic contour
• Trendelenburg and Reverse Trendelenburg function
Lockout management
Patient pendant or caregiver siderail control unit interfacing
Indication of Bed Not in Low Position (see “Detection of Bed Not in Low
Position” on page 3-9)
Indication of Bed Connected to AC Power but Brakes not Applied (see
“Detection of Bed Connected to AC Power but Brakes not Applied” on page
3-16)
All of these functions are integrated into a complex programmable logic device
(CPLD).
Description Specification
Components 2 12 V batteries
Capacity of each battery 1.2 Ah
Voltage 24 V DC
Maximum charging time 12 hours
Discharging time (storage), battery
connected to bed Minimum 10 days
Discharging time (storage), battery not
connected to bed 3 months