HOW TO SET

There are four different ways the Link 20 can approximate time of operation remaining. You may select present consumption level, a four-minute rolling average, a 16-minute, or a 32-minute rolling average. Which method is best for you depends on your installation. Most installations will find the four-minute average appropriate.

1.Press SET for five seconds. SEL will appear in the numeric display.

2.

Press SEL four times.

The

 

light will come on and 001 will

 

 

 

 

appear in the Link 20 numeric display.

3.Press and hold SET. The numeric display will move up in 1 unit steps with choices of:

Instant:

Display:

000

4-Minute Avg:

Display:

00I

16-Minute Avg: Display: 002

32-Minute Avg:

Display:

003

4.After 10 seconds, the displayed setting is stored in memory and normal operation resumes.

INTRODUCTION TO RATE COMPENSATION AND THE PEUKERT EXPONENT

Your Link 20 shows true amp hours consumed in the numeric amp-hour display. However, the light bar above it shows how much of the available battery capacity has been consumed. You may experience times when the light bar shows more than 60% of capacity consumed, yet according to the numeric display less than half of the battery capacity has been consumed. How can this be?

In 1897 a scientist named Peukert demonstrated that as you discharge a battery more quickly, its effective size temporarily decreases. A battery is considered fully discharged when it is no longer able to maintain 10.5 volts under load. As you'll see in the following table showing the effect on a typical liquid cell battery, the faster the discharge rate, the smaller its effective capacity:

Hours to Discharge

Capacity as percent of 20-hr rating

20

100%

10

84%

5

67%

2

56%

1

47%

In other words, a 100 amp-hour battery discharged completely in one hour will only supply 47 useful amp hours.

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