How do I determine the volume values when calibrating gravimetrically?

The most common method involves measuring the mass of distilled water (whose physical properties are known) using a balance, and then converting the mass to a volumetric value. This means that the measurement values from the analytical balance are multiplied by the correction factor Z (see SOP pipettes). This adjustment accounts for the density of water at the specific temperature and the relevant air conditions.

What does EN ISO 8655 cover?

ISO 8655-2022 is the global standard for piston-operated volumetric apparatus (POVA), including pipettes, burettes, dilutors, dispensers, and manual precision syringes, as defined by the International Organization for Standardization (ISO). It ensures standardized performance for manufacturers, calibration providers, and users.It is structured in 10 chapters: ISO 8655-1: Terminology, general requirements and user recommendations ISO 8655-2: Pipettes ISO 8655-3: Burettes ISO 8655-4: Dilutors ISO 8655-5: Dispensers ISO 8655-6: Gravimetric reference measurement procedure ISO 8655-7: Alternative measurement procedures ISO 8655-8: Photometric reference measurement procedure ISO 8655-9: Syringes ISO 8655-10: User guidance, user qualification and POVA qualification.

What do the terms random error and systematic error mean in a pipette calibration?

In pipette calibration, random error and systematic error are two key concepts that help ensure accuracy and precision in measurements. Random Error refers to the variability in measurements when the same volume is dispensed multiple times. It is also known as imprecision and is determined by calculating the repeat standard deviation of 10 measurements. These errors tend to scatter around the true value and can be minimized by consistent technique and proper training. Systematic Error is the consistent deviation of the measured volume from the selected/true volume, also known as inaccuracy and is determined by establishing the mean value of 10 measurements. Systematic errors can arise from defective or misadjusted devices and need to be corrected through proper calibration and maintenance.

Why are the Z factors listed in our SOP different from factors which can be derived from density reference values (of water)?

The Z factor is included in EN ISO 8655-6 and was incorporated into our SOP. As we understand it, it was incorporated in the standard by the Physikalisch Technische Bundesanstalt in Braunschweig. The Z factor describes the density of water at a particular temperature using a 5th degree polynomial. Furthermore, the density of water is corrected by the density of air (derived from air pressure) and a fixed correction value for balances. These corrections are the key reasons for the deviation from density values in various books of tables.

text.skipToContent text.skipToNavigation

CN | CNY

Sorry, we couldn't find anything on our website containing your search term.

Varipette^® 4720 - 大容量移液器

Varipette® 4720 positive displacement pipette from Eppendorf

请注意：本产品已停止销售。

停产日期：1月 2025

下面您将找到支持文件。对于设备，还列出了可用的服务、配件和备件。

替代产品：

Eppendorf Research^® 3 neo

Discontinued product

产品信息

此款移液器自2025年1月起停产，并不再上市销售。为满足您的使用需求，我们承诺在未来数年内继续提供此款移液器专用耗材和配件。此外，Eppendorf服务团队也将继续提供专业校准和维护服务，以确保移液器始终保持完美性能。

显示更多产品信息

了解关于Eppendorf可持续性和人体工程学的更多信息

索取演示版

您可以在以下网址找到其他下载资料本页面底部

产品 (1)

Services (11)

附件 (4)

1 产品

Varipette^® 4720

1-通道
1– 10 mL（连续体积选择）

更多产品详情...

目录编号 4720000011

显示更多产品

已添加到您的购物车

产品信息

用途

特征

适用于较大的瓶子或者较深的窄口容器的大体积外置活塞式移液器。

Varipette 4720大容量外置活塞式移液器由Eppendorf生产，单手操作简单便捷，有助加快移液速度。Varipette 4720移液器采用优化设计，适用于粘性或挥发性、高蒸气压液体，可连续调节。与EppendorfVaritips^® S系统配合使用，它也适用于从较大的瓶子或者较深的窄口容器移取液体，或使用Varitip P型吸头从烧杯中移取液体。

操作极其简单，单手即可完成，可大幅加快移液速度——只需按下Varipette 操作杆即可从储液器中吸取液体；再次按下操作杆，便可将液体注入样品容器中。

产品停产通知：移液器停止销售，但将继续提供耗材和服务

Varipette 4720 正位移移液器已于2025年1月停产，并不再上市销售。为满足您的使用需求，我们承诺在未来数年内继续提供此款移液器专用耗材和配件。此外，Eppendorf服务团队也将继续提供专业校准和维护服务，以确保移液器始终保持完美性能。

请联系您当地的销售代表，探讨如何从我们最新一代液体处理系统中选出合适的替代产品，或登录Pipetting System Finder网络应用程序自行挑选。