How to use the analytical balance?
Release date: 2016-10-24
An important indispensable instrument for quantitative analysis is an analytical balance. Full understanding of instrument performance and proficiency in its use is an important guarantee for obtaining reliable analysis results. There are many types of analytical balances, including ordinary analytical balances, semi-automatic / fully automatic electro-optical analytical balances and electronic analytical balances. At present, electronic analytical balances with a high degree of automation are routinely used in laboratories. How should electronic analytical balances be used? What are the precautions? Let's take a look with Xiaoxi Sister!
General steps and precautions of electronic analytical balance
Rules of use:
The use of electronic balances has high requirements, both for the personnel and the specific environment used, including the following:
Choose the right balance:
When selecting a balance, the first thing to consider is whether there is a special requirement for the accuracy of the symmetrical quantity. We should avoid weighing with an inaccurate balance as much as possible, and we also need to avoid using an overly accurate balance Weighing, resulting in waste of use. In addition, when selecting a balance, in addition to considering accuracy, it is also necessary to consider whether a large number of ranges can meet the needs of weighing. Because according to the different use cases, the selection of the range should also be based on the application, not the bigger the better, the picture shows a common electronic balance.
Preheating is still necessary :
Pre-heating before weighing is not only a method of using the electronic balance, but also one of its characteristics. Only after preheating will the magnetic steel be balanced accordingly and the balance will be balanced. When preheating, the most important thing is to control the preheating time of the balance, and the determination of the preheating time needs to be combined with the calibration graduation value and graduation number of the balance. It can be concluded that, of course, the warm-up time will be slightly different due to the different performances of the balances of various manufacturers. However, in general, the balance needs to be warmed up for more than half an hour before the calibration. It should be noted that the warm-up time of the balance is also closely related to accuracy. The higher the accuracy of the balance, the longer the warm-up time, so be sure to operate according to the instruction manual of the electronic balance, after the warm-up time is reached, the verification can be performed .
① Adjust the level to the height of the foot bolt so that the air bubble in the balance level is located in the center of the ring;
② After turning on the power, press the ON / OFF key until the full screen is displayed;
③ After warming up the balance for the first time, it needs to warm up for 30min after a long power failure;
④ To calibrate, press the calibration key CAL. The balance will display 100.0000. Put the special calibration weight lightly on the ice draft shield. Wait for the screen to display 100.0000. Remove the calibration weight. The screen displays 0.0000. Display 100.0000 ± 0.0001g before use, otherwise it must be corrected again;
⑤ Weighing using the zero key TARE, remove the skin to zero, place the sample for weighing ;
① The electronic balance is warmed up for 30min before starting to weigh;
② Check the air bubbles of the balance at any time and pay attention to whether the balance is level;
③ The balance should be adjusted regularly by a person to ensure the accuracy of the balance at any time;
④ When using a balance to weigh, you should handle it lightly and never allow greater impact and vibration to the balance, especially the weighing pan;
⑤ Be careful not to spill materials into the balance when weighing;
⑥ When opening and closing the door of the balance, the action should be light, and no sound is allowed;
※ How to deal with spilled materials?
A. Find someone with experience;
B. If the situation is urgent, you need to adopt appropriate methods to handle it, and prevent the material from entering the weighing pan during processing. For solid materials, the balance door should be fully opened and blown out with a suction ball; for liquid materials, it should be gently dried with clean filter paper. If it is not dry, it must be handled by an experienced person.
质量 When weighing the balance, the mass of the weighing object must not exceed the range of the balance.
Now, let ’s talk about the performance and usage of PL203 / 01 and AL104 / 01 electronic analytical balances.
PL203 / 01 precision electronic balance: maximum weighing 210g; actual graduation value 0.001g;
AL104 / 01 high-resolution electronic analytical balance: the maximum weighing is 110g; the actual graduation value is 0.0001g.
使用方法： 1. How to use:
1 ）检查并调整天平至水平位置。 ( 1 ) Check and adjust the balance to a horizontal position. 30min 。 Check whether the power supply voltage matches (using the configured voltage regulator), and power on according to the requirements of the balance instrument to warm up to 30 minutes .
2 ）打开天平开关“ on ”，天平则自动进行灵敏度及零点调节。 ( 2 ) Turn on the balance switch " on ", and the balance will automatically adjust the sensitivity and zero point. When all fields on the display light up for a short time, when the balance returns to zero, formal weighing can be performed.
3 ）称量时将洁净称量瓶或称量纸置于称盘上，关上侧门，天平将显示该重量，点击“ ® O/T¬ ”键自动校对零，然后逐渐加入待称物质，直至所需重量为止。 ( 3 ) When weighing, place a clean weighing bottle or paper on the weighing pan, close the side door, the balance will display the weight, click the " ® O / T ¬ " key to automatically calibrate to zero, and then gradually add the substance to be weighed. Until the required weight.
4 ）称量结束应及时除去称量瓶（纸），关上侧门，切断电源，并做好使用情况登记。 ( 4 ) The weighing bottle (paper) should be removed in time after the weighing is completed, the side door should be closed, the power should be cut off, and the use situation should be registered.
注意事项： 2. Note:
1 ）天平应放置在牢固平稳水泥台或木台上，室内要求清洁、干燥，同时应避免光线直接照射到天平上。 ( 1 ) The balance should be placed on a solid and stable concrete or wooden table. The room should be clean and dry. At the same time, it should avoid direct light exposure to the balance.
2 ）称量时应从侧门取放物质，读数时应关闭箱门以免空气流动引起天平摆动。 ( 2 ) The material should be taken from the side door when weighing, and the box door should be closed when reading to prevent air from causing the balance to swing.
3 ）挥发性、腐蚀性、强酸强碱类物质应盛于带盖称量瓶内称量，防止腐蚀天平。 ( 3 ) Volatile, corrosive, strong acids and alkalis should be weighed in a weighing bottle with a lid to prevent corrosion of the balance.
4 ）电子分析天平若长时间不使用，则应定时通电预热，每周一次，每次预热 2h ，以确保仪器始终处于良好使用状态。 ( 4 ) If the electronic analytical balance is not used for a long time, it should be pre-heated at regular intervals, once a week for 2 h each time to ensure that the instrument is always in good use.
Electronic balance is used more and more frequently in daily life. It is made according to the principle of electromagnetic force balance. Therefore, you can weigh directly without adding weights like traditional scales, which is one of the important reasons for its popularity. After placing the object on the scale, the weighing result can be obtained within a few seconds. This article mainly analyzes the correct use of the electronic balance and explains the matters needing attention. At the same time, in order to make better use of the effectiveness of the electronic balance, this article also explores its daily maintenance and maintenance.