Evaluation of Two Fully Rugged Laptop Computers for the Forest Service, Page15

Evaluation of Two Fully Rugged Laptop Computers for the Forest Service

Appendix H—Battery Performance Test

Purpose

Tests were conducted to determine the expected battery life on a single charge when the laptop was subjected to typical usage. Battery life is critical when laptops are used in the field. Longer battery life means field employees won't have to carry as many batteries and won't have to swap or change batteries as frequently. Industry-accepted benchmarking software was used to test the laptops' batteries under several scenarios.

Also, tests determined the expected time to recharge the battery from a full discharge (less than 5 percent battery charge) to full charge (100 percent).

Equipment

MobileMark 2007 is an application that determines expected battery life based on real-world applications. MobileMark has three different testing modules. Each module includes a set of applications that can be run individually to show battery life in a variety of specific scenarios. The productivity module tests the battery life by simulating normal business usage. The DVD module tests battery life while running a DVD. The reader module simulates a person reading a large document on the laptop.

The PassMark Battery Monitor software was used to monitor the battery recharging. It was set to record the battery status every minute.

Procedure

Each of the three MobileMark modules was run on each laptop. The laptops were fully charged before each test. The CF-30 laptop was tested with the screen brightness set to 500 and to 1,000 nits, showing the difference in battery life that might be expected with the brighter screen.

With the battery fully discharged, the laptop was plugged in and the Battery Monitor software was started. A log file was initiated and the laptop was recharged. Logging was stopped when the battery was fully charged (100 percent).

Results

Figure H–1 shows the results of the MobileMark tests. Figure H–2 shows the results of the recharging tests.

Graph of the test results of the Mobile Mark Battery Performance Tests. The test were on the CF-20 (500 nits), CF30 (1,000 nits), and the XR-1 (DynaVue). They were tested on the Productivity Suite, DVD Suite, and Reader Suite.
Figure H–1—MobileMark 2007 battery performance software
was used to measure battery life. The CF-30 battery
lasted nearly twice as long as the XR-1 battery.

Graph of the Battery Charging Time of the XR-1 and CF-30 showing how many minutes it took for each laptop.
Figure H–2—PassMark Battery Monitor software was used
to monitor the battery recharging time for each laptop. It took
more than twice as long to charge the CF-30 laptop
battery as the XR-1 laptop battery.

Conclusions

The battery life of the CF-30 laptop was more than twice as long as the battery life of the XR-1. A user could expect about 6 h of use with the CF-30 laptop when the screen is set to 500 nits. Battery life drops to about 5 h when the screen is set to 1,000 nits. The XR-1 laptop has a battery life of about 2.5 h under most conditions.

Recharging time is significantly different. The CF-30 battery took nearly 8 h to recharge, compared to just a little longer than 3 h for the XR-1 battery.