Assemblies Descriptions B: Theory of Operation
191
Power and Battery
The Efficia DFM100 can be powered by the Battery alone, AC supply alone, or by the Battery and AC
supply together (this configuration is used to charge batteries). The device transitions between power
sources as sources are added and removed without interrupting any operation as long as at least one
source of power is always present.
Battery PCA
The Battery PCA provides the contacts with which the Battery mates. It is an interconnection PCA only,
and has no active circuitry.
Power Supply Assembly
The Power Supply has a standard power connector and operates between 100-240 V AC at 50 or 60 Hz;
it can power the device and charge the battery.
The Power Supply may draw up to 65 watt of AC power, which is then converted to regulated 18 V DC
power. The primary purpose of this supply is to charge the battery, but it can also be used to power the
entire device even in the absence of a battery.
The Power Supply is compatible with world-wide AC mains voltages and frequencies.
Battery
The batteries used in the Efficia DFM100 utilize lithium-ion chemistry. Lithium-ion batteries feature
high energy density, allowing the use of smaller and lighter batteries to achieve high power levels. In
addition, lithium-ion batteries are more environmentally friendly than nickel-cadmium or lead-acid
batteries, and do not suffer from the “memory effect” that plagues nickel-cadmium chemistries.
Each battery pack includes built-in protective circuitry to prevent damage from overcharging, excessive
discharge current, and other types of electrical abuse. It contains circuitry to monitor the amount of
charge available in the battery. The Battery PCA communicates this information to the Therapy PCA
which provides battery status information on the display. In addition, the battery pack has on-board
temperature sensing which is monitored by the Therapy PCA for battery charging purposes.
WARNING: Never crush, penetrate or attempt to open these or any lithium-ion batteries. Never incinerate any
lithium-ion batteries. High case temperatures resulting from abuse of the battery could cause physical
injury. Rupture of the battery pack may cause venting and flame.
CAUTION: Due to their high energy density, the lithium-ion batteries can deliver significant power. Use care when
working with or testing these or any lithium-ion batteries. Do not short-circuit the terminals.
NOTE: When the battery is removed from the Efficia DFM100, it disconnects power to the output terminal.
Thus, it is not possible to test the battery with a voltmeter.
To Next Page
Loading...