Choosing a calibration standard usually comes down to one question: what are you actually calibrating? The four used units here span a wide range, from a B&K 750 null indicator at $49 to a FLUKE 5500A multi-product bench calibrator at $22,500. A lab that maintains electrical test gear has different needs than a technician working with pressure calibration, and the price spread reflects that. The practical move is to match the calibrator's workload, range, and interface to your specific bench or field process.
Quick take
If you run a metrology lab and need one bench instrument for DC/AC voltage, DC/AC current, resistance, capacitance, frequency, thermocouple and RTD simulation, the FLUKE 5500A is the heavy-duty choice. For electric pressure calibration, the Fluke 719Pro 300G is the 300G model, while the Fluke 719 30G covers the lower pressure range. The B&K 750 is a vintage wired null indicator that powers on but has not been tested beyond that, so think of it as a bench project or spare rather than a primary reference.
Listed price comparison
| Product | Best matched workload | Listed price | Relative price |
|---|---|---|---|
| FLUKE 5500A | Bench multi-product electrical calibration | USD 22,500.00 | |
| Fluke 719Pro 300G | Electric pressure calibration with 300G model | USD 2,999.99 | |
| Fluke 719 30G | Low-pressure calibration, -12 to 30 psi | USD 1,200.00 | |
| B&K 750 | Vintage wired null indicator, powers on | USD 49.00 |
Decision matrix
- Bench metrology lab handling DMMs, clamp meters, panel meters, data loggers, process instruments, and temperature measuring equipment: FLUKE 5500A.
- Electric pressure calibration with the 300G model you want: Fluke 719Pro 300G.
- Low-pressure process checks in the unit's confirmed psi band: Fluke 719 30G.
- A vintage, wired null indicator with a confirmed power-on state, for collectors or bench spare parts: B&K 750.
Product notes
FLUKE 5500A
The FLUKE 5500A is a discontinued bench-top multi-product calibrator built for metrology laboratories. It consolidates DC/AC voltage, DC/AC current, resistance, capacitance, frequency, thermocouple and RTD temperature simulation, and AC/DC power simulation into one unit. That makes it a strong fit for calibrating digital multimeters, clamp meters, panel meters, data loggers, process instruments, and temperature measuring equipment. It also supports dual-output mode and includes GPIB and RS-232 remote interfaces, so it can drop into automated calibration systems. Optional SC300 or SC600 modules add oscilloscope calibration capability. The real constraints are the lab-oriented footprint, the used condition, and an asking price that puts it at the top of this group. Plan for dedicated bench space and a workflow that can use its breadth.
Fluke 719Pro 300G
The Fluke 719Pro 300G is a used electric pressure calibrator in the 719 Pro line, sold as a calibrator only after being pulled from the field for an upgrade. For a technician who needs an electric pressure calibrator with the 300G model designation, this is the direct match among the pressure units here. It is sold as calibrator only, with everything pictured only, so you will need to supply any leads, fittings, or carrying case that are not part of the pictured package. That unit-only packaging is the main limitation. If you are upgrading from an earlier 719, the Pro 300G is the model to look for, but be ready to assemble the kit around it.
Fluke 719 30G
The Fluke 719 30G is an electric pressure calibrator with a clearly defined range of -12 to 30 psi. That makes it a natural fit for low-pressure process checks, pneumatic systems, and instruments that live in that psi band. The focused range is also the limitation: if your equipment operates above 30 psi, this unit will not be the one. It is a used instrument, so inspect the condition before you rely on it as a primary standard. For shops that need exactly this low-pressure window, the 719-30G is a worthwhile, straightforward choice.
B&K 750
The B&K 750 is a used, wired null indicator in blue, sold as a vintage test equipment calibrator. The one confirmed behavior is that it powers on, and no other tests have been performed beyond that. The unit also shows scratches and imperfections typical of age. That places it as the least demanding option in terms of upfront commitment. The unknown electrical behavior is the hard limitation, so it should not be treated as a reference standard. Think of it as a project unit, a power-on demonstrator, or a parts source rather than something to certify equipment against.
Final recommendation by use case
- If your lab needs one broad, automation-ready electrical calibrator and can absorb the bench space and top-of-range price: FLUKE 5500A.
- If you need an electric pressure calibrator and the 300G model is the one you want: Fluke 719Pro 300G, with the calibrator-only caveat in mind.
- If your pressure tasks stay within the low-pressure band of the 719 30G: Fluke 719 30G.
- If you are shopping for a vintage wired null indicator and a confirmed power-on state is enough: B&K 750.
