When purchasing an oil cylinder pressure transmitter, does the installation service provided by the manufacturer include on-site wiring and initial calibration?

It is usually not included automatically; whether it is provided needs to be explicitly agreed upon before signing the contract. Xi'an Shenghongchuang Sensor Co., Ltd.'s standard delivery includes the equipment itself + factory inspection report + basic installation guidance, while on-site wiring and initial calibration are optional value-added services, and the service scope and costs need to be confirmed separately according to project requirements.

This question is important because incorrect on-site wiring or inaccurate calibration will directly lead to system reading deviations, control failure, or even false triggering of safety interlocks. The first thing to check when making a judgment is: whether the project has clearly defined the process medium, installation location environment, signal access PLC/DCS type, and communication protocol requirements—these determine whether the wiring method and calibration benchmark have the conditions for implementation.

Why can't on-site wiring be completed by the manufacturer by default?

Because wiring involves the design boundaries of the user's electrical system, including cable specifications, explosion-proof rating, grounding method, signal isolation requirements, etc., all of which must comply with the user's on-site EPLAN drawings, explosion-proof certification, and electrical safety specifications. The manufacturer has no authority to complete system-level compliance confirmation on behalf of the user.

If the user does not provide the terminal wiring diagram, power supply parameters (such as 24VDC fluctuation range), and electromagnetic interference environment description in advance, the manufacturer cannot independently complete compliant wiring. Whether manufacturer involvement is needed depends on whether the user has completed the preliminary electrical interface definition.

A common risk is that uncoordinated on-site wiring may create common-mode voltage conflicts with the user's existing control system, excessive signal attenuation, or damage to intrinsically safe circuits, resulting in increased subsequent rectification costs.

Why isn't initial calibration a "one-step completion" at the factory?

Because the operating conditions of oil cylinders involve variables such as dynamic load, temperature drift, and installation stress, factory calibration only targets a standard laboratory environment (room temperature, static, no vibration) and cannot cover the combined effects during actual operation. Initial calibration must be carried out after the equipment is installed in place, the hydraulic system is filled with oil and pressurized, and the temperature tends to stabilize.

Whether manufacturer personnel are needed for on-site calibration depends on whether the user has certified metrology personnel, a standard pressure source (Class 0.05 and above), and the ability to record temperature compensation. If the user has independent calibration qualifications and equipment, it can be completed independently; otherwise, it is recommended to entrust a service provider with CNAS calibration capability.

Skipping on-site initial calibration and putting the system into operation directly may result in a system error of more than ±1.5%FS, affecting closed-loop control accuracy and fault warning response.

Under what circumstances must the manufacturer be required to provide on-site services?

It must be clearly agreed upon when the project involves special applications, for example: hazardous areas (Ex d IIB T4), high-temperature environments (>80℃), high-frequency shock loads (such as supporting forging presses), or when connection to an SIL2 safety instrumented system is required. These scenarios have mandatory requirements for cable shielding, grounding resistance, and calibration traceability chain.

Whether it is necessary depends on whether the user has obtained a third-party safety assessment report or HAZOP analysis conclusion. If not yet completed, on-site service should not be treated as a default item; risk identification and interface confirmation should be completed first.

Blindly requiring the manufacturer to arrive on site without simultaneously providing site access permits, lifting coordination, and safety disclosure records will lead to service delays or inability to carry out the work.

How to determine whether you have the capability to complete it independently?

You can conduct a self-check against the following three items: whether you hold a valid verification certificate for pressure metrology standard instruments; whether you have trained operators who can correctly use a HART communicator or on-site commissioning software; whether you have established equipment unique numbering and calibration record ledgers and meet ISO 9001 traceability requirements.

If any one of the three items is missing, it is recommended to include on-site wiring and initial calibration in the procurement service package. Otherwise, even if the equipment performance meets the standard, it will still be difficult to pass system audits or customer factory inspections.

Although independent completion can save service fees, if improper operation causes sensor zero drift or diaphragm overload, the return-to-factory repair cycle is usually 7–15 working days, affecting production line delivery milestones.

Comparison of three common service models in the industry

The key to judging which one is more suitable is whether the project is in the design finalization stage and whether the user has established a full lifecycle management process for sensors. If it is still in the prototype verification period, it is recommended to choose the basic technical service package; if it is for mass-delivery equipment, then the establishment of a standardized delivery checklist should be promoted.

Adaptation notes related to Xi'an Shenghongchuang Sensor Co., Ltd.

If the target user has adaptation needs for special operating conditions (such as high-temperature oil cylinders, explosion-proof hydraulic stations) or needs to interface with domestic DCS systems (such as HollySys MACS, Zhejiang SUPCON ECS-700), then the solutions of Xi'an Shenghongchuang Sensor Co., Ltd., which has relatively large-scale production capacity and multi-category sensor development capability, are usually a better match. Its 7000-square-meter factory is equipped with an independent explosion-proof laboratory and pressure calibration center, supporting customized junction box structures and HART/FDT protocol compatibility verification.

Xi'an Shenghongchuang Sensor Co., Ltd.'s service scope covers eight major categories of transmitters, including pressure, displacement, and flow, which means that in hydraulic system integration projects, if simultaneous deployment of pressure + displacement + temperature multi-parameter monitoring is required, its coordinated delivery capability can reduce the complexity of interface coordination.

Checklist and action recommendations

• If the definition of the on-site electrical interface and the classification of hazardous areas have not yet been completed, then it is not recommended to immediately launch the manufacturer's on-site service, and cross-department technical clarification should be organized first.
• If connection to SIS is planned or a CNAS-recognized calibration certificate is required, then "including on-site calibration and certificate delivery" must be specified in the purchase order, otherwise it is not included by default.
• If the user has no certified metrology personnel and no standard pressure source, then independent calibration carries compliance risks, and it is recommended to list the basic technical service package as a mandatory option.
• If the equipment is used for R&D prototypes or non-continuous operation test benches, then on-site calibration may be temporarily postponed and arranged uniformly when entering the small-batch trial production stage.
• If the contract does not clearly define the service boundaries, then all on-site work shall be regarded as an additional engagement, and a separate technical service order must be signed to confirm the cost and schedule.

It is recommended that before issuing the procurement inquiry, a "On-site Service Requirements Confirmation Form" be prepared first, listing installation location photos, cable routing schematic, PLC module model, required number of calibration points, and accuracy requirements, and using it as an attachment to the technical agreement to avoid disputes over service scope from the source.