Digital Hydraulic Pressure Gauge Alternatives: How to Compare STAUFF, PDK and Baroli

Quick answer: if you are looking at a STAUFF digital pressure gauge for hydraulic testing, the sensible way to compare alternatives is on eight facts: accuracy and its basis, pressure range, process thread and test-coupling compatibility, data logging, units and features, ingress protection, calibration certificate, and local support. STAUFF’s SPG-DIGI series, for example, is published with a typical accuracy of 0.25% and a maximum of 0.5% of full scale, ranges up to 600 bar on its current product page (distributor listings also show a 1,000 bar version) and an optional internal data memory. The PDK gauges we supply cover 0.5% down to 0.025% of full scale, with ranges up to 700 bar and optional or built-in logging on the higher models. This guide explains how to compare digital hydraulic gauges fairly, and which suits which job. It uses publicly available datasheets, so check current versions before ordering.

Why compare at all?

A digital hydraulic gauge is a small investment compared with the machines it protects, but the wrong one causes delays: a thread that does not fit the test point, a range too low for a spike, accuracy that cannot verify a tight tolerance, or no logging when you need to find an intermittent fault. A short, factual comparison before you buy avoids all of these.

The eight comparison points

1. Accuracy and how it is stated

Accuracy is usually a percentage of full scale (% FS). Check whether the figure is the typical or the maximum, and whether it covers temperature effects. The STAUFF SPG-DIGI datasheet gives a maximum of 0.5% and a typical value of 0.25%, both of the end value of the range. The PDK PDR range is stated at 0.5% (PDR100), 0.25% (PDR250), up to 0.1% (PDR500) and 0.025% (PDR1000). See accuracy compared in real numbers for how to turn those into bar.

2. Pressure range

STAUFF’s current SPG-DIGI product page lists ranges from -1 to 600 bar, including a low-pressure -1 to 5 bar version, and distributor listings also show a 1,000 bar version. The PDR100 covers compound -1 to 2 bar and 0 to 10 up to 0 to 100 bar. The PDR250 covers 0 to 10 up to 0 to 700 bar. The Baroli BD Series spans 0 to 100 mbar up to 0 to 600 bar. For hydraulics, choose a range around 1.5 times the working pressure and check the overpressure rating. See the range selection guide.

3. Thread and test-coupling compatibility

Hydraulic test points commonly use minimess-type couplings and adaptors. The SPG-DIGI is listed with a G1/4 connection and with adaptors available for STAUFF Test couplings. Other thread options may exist on some variants, so check the exact model. The PDR100, PDR250 and PDR500 use a G1/4 BSPP male bottom-entry connection, and the PDR Digital Pressure Test Kit includes 1/4″ BSPP, 1/8″ NPT, 1/4″ NPT, 7/16″ UNO and 9/16″ UNO adaptors and a 2 metre hose. Whichever gauge you choose, check that you can connect it to your machines’ test points without improvised fittings.

4. Data logging

The STAUFF USB version stores readings in an internal memory and is described as having a maximum measurement duration of 24 hours per measurement. The PDR500 offers optional datalogging, and the PDR1000 has built-in logging. If you need to capture a spike or an intermittent fault, check the logging interval and memory on the datasheet, because those details decide how useful the log is.

5. Units, min/max and features

Look for selectable units, minimum and maximum capture, auto-off and a zero function. The PDK gauges offer units including mbar, bar, MPa, mmH2O, inHg, mmHg, kgf/cm2, atm, psi and kPa, plus min/max recording and a calibration function.

6. Ingress protection and durability

Workshops are rough on instruments. The PDR500 is rated IP66 and comes with a silicone cover, and the Baroli BD Series is IP65. Check that the stated rating applies in use. STAUFF’s product page does not state a protection rating, so ask the supplier for it in writing.

7. Calibration certificate and traceability

If the gauge is used to verify settings, ask whether a calibration certificate is available and what it covers. Some suppliers list calibrated variants separately.

8. Support and spares

Ask who supports the gauge in Australia, how long adaptors and seals are available, and what the warranty covers. See our supplier checklist.

Side-by-side summary

The STAUFF column is taken from public STAUFF information (a product spotlight and datasheet dated 2020 and 2021), so check the current manufacturer datasheet before specifying. The PDK figures come from our product datasheets.

Which suits which job?

Field technician fixing machines

You need a gauge that survives a ute and gives a trustworthy reading, with the right adaptors. The PDR250 with a test kit, or any gauge of similar class that fits your test points, works. See digital hydraulic pressure gauges.

Maintenance team checking relief valves

Use the four-to-one rule: the gauge must be four times more accurate than the tolerance. For a 210 bar valve with a 5 bar tolerance on a 0 to 400 bar range, a 0.25% gauge (1 bar) qualifies, while a 1% gauge (4 bar) does not.

Intermittent fault hunting

Choose a gauge with logging, and check the sample rate. A fast spike lasting a fraction of a second needs a fast logger, so the memory and interval matter more than the headline accuracy.

Calibration bench

Choose the PDR500 or PDR1000 and have it calibrated by an accredited laboratory. See pressure gauge calibration.

Total cost of ownership

• Purchase price, including adaptors and hose if not supplied.
• Calibration cost and frequency.
• Battery type and life.
• Cost of downtime caused by a gauge that does not fit.
• Ease of getting spares and support.

Questions to ask any supplier

1. Is the accuracy typical or maximum, and does it include temperature?
2. What is the overpressure rating?
3. Which threads and adaptors are included?
4. What are the logging interval and memory?
5. Is a calibration certificate available?
6. What is the warranty?

Worked example: choosing for a service fleet

A hydraulic service business runs five vans. Each technician needs one gauge that connects to the test points on mobile plant, handles pressures up to 400 bar, is accurate enough to check 5 bar tolerances, and survives being thrown in a tool box. The business compares: accuracy (0.25% FS gives 1 bar on 0 to 400 bar, which meets the four-to-one rule), thread (G1/4 BSPP and the adaptors in the test kit), logging (not needed for spot checks, so no premium paid), and protection (a rubber cover). It picks the PDR250 with a test kit for each van, and one PDR500 in the workshop as a reference, which is sent for accredited calibration each year. The reference is used to check the van gauges every six months.

Adaptors, hoses and couplings

• Check the hose pressure rating exceeds the highest test pressure.
• Carry the thread types you meet most: 1/4 BSPP, 1/8 and 1/4 NPT, 7/16 and 9/16 unified.
• Replace worn bonded seals and O-rings routinely.
• Use test couplings that match the machine’s test points, which is a separate check from the gauge thread.

Battery and care

Keep a spare battery in the case. Remove the battery before long storage. Store the gauge capped, away from heat, and bleed pressure slowly before disconnecting. After any suspected overpressure event, check zero and compare with a reference before relying on the gauge again.

Reading datasheets without being misled

• Typical vs maximum: a typical accuracy figure is better than the guaranteed one. Compare like with like.
• Range-dependent accuracy: some makers state different accuracy on low ranges. Check your range specifically.
• Temperature: check whether accuracy applies over the full operating temperature range or only at 20 degrees Celsius.
• Overpressure: two gauges with the same range can have different overpressure ratings.
• Calibration: a gauge listed with a calibration certificate is a different line item from one without.

Support and warranty questions

Ask who supports the gauge in Australia, whether adaptors, seals and batteries are readily available, what the warranty covers and how long a repair or replacement takes. For a field technician, a gauge that is back in two days is worth more than a slightly better one that takes three weeks.

Making the decision

List your three must-haves, for example 400 bar range, G1/4 BSPP thread and 0.25% accuracy. Remove any gauge that misses one of them. Then compare the remainder on logging, protection and support. This avoids being swayed by extras you will not use.

Stauff figures in this guide were rechecked on 5 November 2026 against STAUFF’s product spotlight and a trade article: accuracy 0.5% maximum and 0.25% typical of full scale, ranges to 600 bar on the current page, up to ten stored measurement series, a maximum measurement period of 24 hours per series, and values shown in bar, PSI, MPa, kPa and mbar. Always confirm against the current datasheet.

Frequently asked questions

Is a PDK gauge a STAUFF equivalent?

We do not claim equivalence. Compare the datasheets for range, accuracy, thread, logging and approvals for your own application.

Can I use my existing test hoses?

Often, if the thread and coupling match. Check the thread before you order.

Which gauge has the best accuracy?

Among those compared here, the PDK PDR1000 at 0.025% FS.

Do I need logging?

Only if you need to record pressure over time. For spot checks, min/max memory is often enough.

Can you help me choose?

Yes. Send your pressure, thread and accuracy needs through the contact page.

Next steps

Read the digital pressure gauge buying guide, pressure sensors for hydraulic systems and browse the digital pressure gauges.