7.4V 3350mAh Electronic Total Station with DS2781 DS2438 MAX17215

A total station (TS) or total station theodolite (TST) is an electronic/optical instrument used for surveying and building construction. It is an electronic transit theodolite integrated with electronic distance measurement (EDM) to measure both vertical and horizontal angles and the slope distance from the instrument to a particular point, and an on-board computer to collect data and perform triangulation calculations.^[1]

Robotic or motorized total stations allow the operator to control the instrument from a distance via remote control. This eliminates the need for an assistant staff member as the operator holds the retroreflector and controls the total station from the observed point. These motorized total stations can also be used in automated setups known as Automated Motorized Total Station (AMTS).

Flaw detector is a portable industrial nondestructive flaw detector. It can detect, locate, evaluate and diagnose various defects (welds, cracks, inclusions, folds, pores, sand holes, etc.) in the workpiece quickly, conveniently, undamaged and accurately. It can be used in both laboratory and engineering site. The instrument can be widely used in manufacturing, iron and steel metallurgy, metal processing industry, chemical industry and other fields that need defect detection and quality control. It is also widely used in in-service safety inspection and life evaluation in aerospace, railway transportation, boiler and pressure vessel and other fields. It is a necessary part of nondestructive testing industry. Portable flaw detector has become an important tool for field testing in modern society, and providing efficient, portable, portable and sufficient backup power solution for portable flaw detector is an important guarantee for testers to carry out long-term field work. Because of its unique advantages, 18650 lithium battery pack has become the first choice for the backup power solution of such high-tech test instruments.

2、 Lithium battery design scheme:
1) Intelligent power meter protection board (PCM): it adopts 1 wire intelligent battery management system, uses advanced power calculation principle to accurately calculate the power of the battery from time to time, reports the power information of the battery to the host from time to time through 1 wire, and provides functional protection to the rechargeable intelligent battery pack. Due to the chemical characteristics of lithium battery, overcharge, over discharge, short circuit Over current, over temperature and other protection functions to avoid combustion, explosion and other hazards.
2) 18650 lithium ion cell / 18650 / 3400mah / 3.7V Li ion cell (Sanyo).
3) Temperature switch: mainly designed for temperature protection function. When the temperature of the battery itself reaches 70 & plusmn due to other abnormal problems; When the temperature is within 5 ℃, the temperature switch acts for temperature protection.
4) Field effect transistor (MOSFET): MOSFET, which plays a switching role in the protection circuit, will never increase or decrease the voltage at both ends of the load, so as to ensure the stability of the voltage.
5) Battery pack package (shell) (ultrasonic welding)