The word “calibrator” is commonly used to describe a portable digital self-contained electronic calibrator, rather than a mechanical device such as a deadweight tester or comparator with test gauges. Deadweight testers have their own section, so here we look at electronic calibrators, and also comparators for use with test gauges. (To review an article on choosing a calibrator, click here)

We have an extremely wide offering in this field, from Ametek-Jofra and DH Budenberg.

From DH Budenberg, there are two versions of the popular portable calibrator designed for use on a flat surface, whether a workbench or plant catwalk. Both of these are full-function portable calibrator weighing just 5 kg. They come with software to link up to a PC, and can power and read analogue electrical instruments directly. PPS40 is a single channel unit, PPS41 is a dual channel unit.

The P540 and H540 calibrators are bench type versions of the PPS40, built around the bases of the 550 or 580 series deadweight testers.

The PPS20 is a new handheld documenting pressure calibrator which can connect to a wide variety of external pressure modules, including environment monitoring, gauge absolute and differential pressure, and electrical. HART communication is an option.

From Ametek-Jofra, the CPC and APC units are classed together. These are hand-pump operated calibrators with the ability to read electrical transmitters but not power them. The Compact CPC is the entry level device, while the Advanced APC offers extended working range with its greatly improved accuracy statement. A pressure switch test function is very useful. The units offer multiple pressure units. The APC will shortly be able to link with the well-known Jofracal calibration software.

The IPI is basically a pressure calibrator without electrical functions, packaged as a digital pressure gauge, yet offering 0,05%FS accuracy, and multiple pressure units, making it ideal for in-process work

For those who need absolute measurement, multiple ranges and better accuracy, Jofra have introduced the new DPC-500 documenting pressure calibrator. This introduces the concept of the “separate” pressure sensor, which can be fixed to the instrument, or used remotely with a cable link. The unit runs pre-defined calibration worksorder and in conjunction with Jofracal software, can generate traceable calibration certificates.

For those who want to build their own bench mounting systems, Budenberg offer pneumatic and hydraulic comparators, again based on the 550 and 580 series bases. These can be used with analogue or digital test gauges.

Finally, for those that demand the best, the DPG series combine the flexibility of the electronic calibrator with the accuracy and stability of the pressure-mass balance. Force is applied via a piston and cylinder onto a precision electronic scale, which allows calibration checks using a simple mass-piece, and provides accuracy in the region of 15 ppm. Two versions exist, the DPG5 for gauge pressure work, and the DPG8 for absolute pressure work.

Useful links:

Ametek Denmark www.jofra.com
Dh Budenberg www.desgranges.com