NorthEast Monitoring, Inc. NEMM019-Rev-O
Page 27 of 35
DR200/HE & DR300 Operator’s Manual
Appendices: Appendix B: Batteries
Appendix B: Batteries
The recorder uses one AA-size battery. This
requirement may be fulfilled in a number of
ways. Battery types available on the market are:
• Alkaline (example: Eveready Energizer E91,
Duracell NM1500)
• Heavy Duty
• Nickel Metal Hydride (example: MAHA AA
1800 mAh, Rayovac 1600 mAh NiMH)
• Nickel Cadmium (NiCd)
Alkaline
The alkaline is the most common type of battery.
When a new, properly stored battery is used, a
recording time of 30 days can be expected in
event mode and 14 days in Holter. When the
DR300 is used in wireless mode, Holter record-
ing can be expected to be up to 7 days before a
new battery is required.
While a recording that runs for 24 hours will in
theory use less than half the capacity of the bat-
tery, using a battery for two different patients’ 24-
hour recordings is not recommended. The risk is
that the "second" recording will not reach 24
hours.
The primary limitation of this battery type is that
there is only a limited ability to test the battery
before it is used. Unfortunately, at times a defec-
tive battery will appear to initially have full
capacity, but will fail well before the expected
time. The probability of this type of failure is
very small when the batteries are obtained from
the primary suppliers.
The best prevention available against defective
batteries is to obtain them from suppliers who do
not store them for a long time and do store them
properly. There are few requirements for storage
of alkaline batteries. They should be stored at
"room" temperatures (50-90 F) and in a dry loca-
tion. There is no advantage to storing them in a
refrigerator. There is actually a significant prob-
lem with low-temperature storage. Normal refrig-
erators have a very high humidity inside and this
can cause a much greater reduction of life that is
gained by the lower temperatures. In addition,
storage at a temperature below freezing will
reduce battery life.
Heavy Duty
Batteries that are labeled "Heavy Duty" vary
widely in capacity. The use of "Heavy Duty" bat-
teries is not recommended.
Nickel Metal Hydride (NiMH
)
This class of batteries is rechargeable and thus
can be used in situations where a disposable bat-
tery is not desirable. Batteries of this type come
in a range of capacities with the labeled capacity
ranging from 1100 to 1800 mAh (milliamp
hours). It is recommended that only batteries with
a rating of at least 1500 mAh be used. Lower
capacity batteries will operate the recorder for 7
days when they are new but after only a few uses
may not be able to operate for the full 7 days.
Recording time on the DR300 in wireless mode
will be significantly less than when used non-
wirelessly.
Charging these batteries is the most difficult part
of their use. Only standard chargers that are spe-
cifically rated for use with NiMH batteries should
be used such as the MAHA MH-204F or Rayo-
vac 1-Hour charger; although medically-
approved chargers can be used, they are not nec-
essary. Older chargers designed only for NiCd
(Nickel Cadmium) will overcharge this type of
battery and can significantly shorten battery life.
A charger that applies an excessive continuous
charge can also shorten the battery life. If in
doubt it is best not to leave the batteries on charge
for long periods of time after the charger indi-
cates a full charge.
Unlike the older rechargeable battery types,
NiMH batteries have no real "memory." Thus
they do not need to be completely discharged or
"conditioned" to insure that they will fully
charge. Doing a complete discharge will reduce
the total life of the battery as every time the bat-
tery is discharged below about 25% capacity, the
life of the battery is shortened more than for a
normal discharge cycle.