HP 4935A, Руководство по эксплуатации и обслуживанию

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General Information Model
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BATTERY OPERATION (Options 001 and 003)
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Nickel-Cadmium batteries enable the 4935A to be used in areas removed from AC power.
Typical operating time hrs when fully charged.
The batteries are trickle-charged whenever the
instrument is connected to an AC source and the POWER switch is in STBY.
Regular discharge-charge cycles are recommended to maintain battery capacity. The instrument
should be operated until batteries are discharged (instrument stops working) then recharged, at least every
30 days. Normal recharge time is about 17 hours. Typical battery life under normal operating conditions
should he at least 100 charge-discharge cycles.
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Charging the Batteries
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The internal battery pack consists of three rechargeable battery packs and
These provide typically 2.5 hours of continuous use without recharging. To recharge the battery packs, connect
the 4935A to an AC
power
source and press the power switch to STBY. Normal recharge
time is about 17
hours.
I-28. The batteries may be charged at temperatures between 5°C and (41°F and but have
greater charge capacity if charged between and 25°C and At temperatures above 25°C
the acceptance
as shown in Figure For example, a cell charged at 45°C accepts about
of its rated capacity. Temperatures below 5°C cause pressure to build up within the cell as it is
charged, which could result in venting of the cell. This results in a permanent degradation of the battery
capacity due to loss of electrolyte.
l-29. Operating Temperature
Normal operating temperature of the I-IP 4935A with batteries (options and 003) should be
between and However, there will be a loss of capacity when operating at the extremes. At low
temperatures, the batteries cannot fully discharge even if they were fully charged at room temperature. At high
temperatures this same effect take
to a lesser degree, in addition to the problem of charge acceptance
previously mentioned.
100% EFFICIENCY
U
40 80 120 160 200
CHARGE INPUT (% OF NOMINAL CAPACITY) CHARGE RATE
0 2 4 8 12 14 16 18 20
CHARGING TIME IN HOURS
CHARGE RATE
Figure 1-2. Charge Acceptance at Various Temperatures
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