Teledyne 4220 - Manual (Page 24)

4220 Flow Meter
Section 1 Introduction
1-10
1.7 How to Make Battery
Calculations
To calculate battery life expectancy for an installation, you must
know two things:
• The capacity of the battery you are using
• The average current draw of the flow meter or (other
device) powered.
Compensated Temperature Range 32° to 122°F (0° to 50° C).
Temperature Error (over compen-
sated temperature range) 0.1 to 4.0 ft. (0.03 to 1.2 m) ±0.005 ft. per degree F
4.0 to 10.0 ft. (1.2 to 3.1 m) ±0.007 ft. per degree F
Table 1-3 Technical Specifications for the 3222 Submerged Probe (Continued)
Table 1-4 Chart Longevity
Chart Speed, Inches/Hour Time to Empty Roll
4 195 Hours (8
1
/ 2 Days)
2 16
1
/ 4 Days
1 32
1
/ 2 Days
0.5 65 Days
Note: Times assume Report Generator is turned off.
Table 1-5 Battery Life Expectancy
1
Flow Meter Settings Minimum Default
2 Maximum
Reading Interval 5 Minutes Continuous Continuous
Printer Off Off 4” per Hour
Report Generator Off Off Every Hour
Average Current 14 mA 9 mA 23 mA
Nickel-Cadmium
3
10.7 Days
5
16.6 Days 6.5 Days
Lead-Acid 4 17.4 Days 27 Days 10.5 days
Notes:
1. These figures are approximations based on calculations; actual times for your flow meter may vary due to
factors of battery age, charge condition, operating temperatures, and component differences. “Minimum” set-
tings are those providing the lowest average current draw. “Maximum” settings are those requiring the highest current
draw. Your program should draw somewhere between the two.
2. The default settings are the program entered at the factory. You can reset the flow meter to the default program at
any time by holding down the 1 and Clear Entry keys at the same time.
3. The nickel-cadmium battery has a capacity of 4.0 ampere-hours at 20° C.
4. The lead-acid battery has a capacity of 6.5 ampere-hours at 20° C.
Both batteries are assumed to be fully charged with at least 95% of rated capacity and in good condition. These cal-
culations also assume a 5% safety factor at the end of discharge. Lead-acid batteries should never be completely
discharged.
5. All fractional times are rounded down, rather than up.