Laboratory pH Meter Series Manufacturer

Shanghai Qiujing Biochemical Reagent & Instrument Co., Ltd. is a China Laboratory pH Meter Series manufacturer and OEM/ODM factory. We have developed and produced laboratory instruments in Shanghai since 1988, supported by a CE and ISO 13485 certified quality management system.

The series currently covers two benchtop platforms, the Qiujing P901 and the Qiujing PHS-3C, and sits inside our broader Laboratory Instruments programme alongside balances, photometers, centrifuges, stirrers and water baths for the same bench.

Two Benchtop Platforms in the Series

Both models measure hydrogen-ion activity in aqueous solution with a pH-responsive glass electrode and a reference electrode, and both are configured for bench work rather than portable field use.

Electrode type, temperature compensation and the buffer routine are agreed per project, because the meter body and the electrode together determine the reading quality on the bench.

Where the Range Fits

Benchtop pH measurement appears wherever an aqueous sample has to be characterised before a decision is made. The configurations in this series are used across:

• Drinking water, wastewater and environmental monitoring — grab samples, treated effluent checks and field samples returned to the laboratory.
• Food and beverage testing — sauces, dairy, syrups and semi-solid preparations where a flat-surface electrode responds faster than a bulb.
• Chemical and industrial R&D — reaction monitoring, formulation trials and raw material checks.
• Pharmaceutical and biotechnology quality control — buffer preparation, media checks and in-process sample measurement.
• University and institutional teaching laboratories — undergraduate practicals that need a durable, splash-resistant bench instrument.

Electrodes, Temperature and the Accuracy Chain

A pH measurement is a potential difference. The glass electrode develops a charge tied directly to hydrogen-ion activity, nominally 59.2 mV per pH unit at 25 °C, and the instrument reads that difference against a stable reference electrode such as silver/silver chloride. Anything that disturbs the electrode pair shows up as drift, slow response or a slope that no longer passes calibration.

• Junction condition — clogged reference junctions cause unstable readings, especially in oily, protein-rich or high-solid samples.
• Temperature — the electrode slope changes with temperature, so automatic temperature compensation is used where samples are not held at 25 °C.
• Calibration buffers — measuring against pH 4.00 / 6.86 / 9.18 or 4.01 / 7.00 / 10.01 sets keeps the slope check consistent with the standard the laboratory reports against.
• Sample matrix — low-ionic-strength waters, viscous pastes and semi-solids each call for a different bulb and junction design.

Critical Specifications We Confirm Before Production

Each order is locked against a specification sheet so that repeat shipments behave like the first one. The items we confirm with the customer include:

• Measuring mode, display resolution and mV capability for the intended routine
• Calibration point count and buffer recognition behaviour
• Temperature compensation method and probe type
• Electrode connector, cable length and stand or holder arrangement
• Housing protection level for the bench environment
• Data output mode — printing, wireless transmission or onboard storage
• Power input, plug type and supplied accessories

Configuration Options and What They Change

Data Handling, Quality Control and Acceptance

The P901 carries a 6.5-inch LED screen with wireless Bluetooth printing and built-in mass storage, so measurement records can be issued and retained at the bench. The PHS-3C pairs its IP54 housing with wireless Bluetooth transmission for labs that move readings off the instrument.

Manufacturing is managed under a CE and ISO 13485 certified system, with raw material inspection, in-process testing and finished-product inspection applied across the production run. Our in-house test laboratory verifies instrument behaviour before release, and sample units can be provided for performance verification before a specification is finalised.

Installation, Commissioning and Maintenance

• Allow a level bench area with room for the electrode holder, beaker and any printer used with the instrument.
• Store electrodes in the reference electrolyte between measurements; a dry bulb is the most common cause of slow or drifting readings.
• Rinse the electrode with deionised water and blot — never wipe — before each sample and each buffer.
• Calibrate at the interval the laboratory's own procedure sets, and re-check the slope after cleaning a fouled junction.
• Electrode replacement is the primary wear item, and repeat orders are matched to the original electrode configuration.
• Operation guidance and troubleshooting support are provided for overseas partners after delivery.

Information We Use to Configure Your Solution

A workable quotation follows from the measurement routine, not from a model name alone. We prepare the configuration and price from the following project inputs:

• Sample type, matrix and expected pH band
• Sample temperature and whether automatic compensation is required
• Accuracy, resolution and repeatability target, plus the calibration routine already in use
• Number of benches or stations and any spare instrument requirement
• Record keeping — printing, wireless transmission or onboard storage
• Bench environment, including splash, dust and humidity exposure
• Power input and plug type for the destination market
• Documentation language, branding and packaging requirements
• Order volume, delivery schedule and destination port

OEM/ODM work covers specification adjustment, appearance, labels and packaging. Samples are available for verification, and standard production lead time for established configurations is 10 working days, with the schedule confirmed at order review.

Frequently Asked Questions

Which models make up the Qiujing laboratory pH meter series?

Two benchtop platforms: the Qiujing P901 with a 6.5-inch LED screen, wireless Bluetooth printing and built-in mass storage, and the Qiujing PHS-3C with an IP54 dustproof and splashproof housing and wireless Bluetooth transmission.

Can the P901 print measurement records directly at the bench?

Yes. The P901 supports wireless Bluetooth printing, and its built-in mass storage keeps measurement data on the instrument as well.

Is the PHS-3C suitable for a wet bench or shared teaching laboratory?

The IP54 dustproof and splashproof design is intended for exactly those conditions, where spills and airborne dust are part of daily use. It is built to comply with four referenced standards and transmits readings wirelessly by Bluetooth.

Do you supply pH meters under our own brand?

We provide OEM/ODM customization on laboratory instruments, covering specification adjustment, appearance, labels and packaging. Distributor and private-label projects are handled through the same configuration process as standard orders.

How do you handle calibration and electrode wear?

Calibration follows the buffer set and interval agreed with the customer, and the electrode configuration is recorded with the order so replacement electrodes match the original specification. Junction cleaning and electrolyte refilling extend electrode life in demanding sample matrices.

What does Qiujing need to prepare a quotation?

Sample type, expected pH range, temperature conditions, record-keeping needs, bench environment, power requirements, documentation language, quantity and delivery schedule. With those points confirmed, we issue the instrument configuration, accessory scope, packaging arrangement and production lead time.