In the actual use of wireless transmission pressure transmitters in factory sites, are data packet loss or delays frequent?

Under the premise of standardized deployment, controllable environmental interference, and matched communication protocols, mainstream industrial-grade wireless transmission pressure transmitters usually do not experience frequent packet loss or obvious delays at factory sites. Whether it occurs mainly depends on wireless channel quality, equipment selection compatibility, the on-site electromagnetic environment, and the rationality of network configuration, rather than being an inherent defect of wireless transmission itself.

The reason this question is critical is that what users really need to determine is not “whether problems may occur”, but “whether my site belongs to a high-risk scenario”. Priority should be given to checking signal coverage strength, metal shielding density, the number of same-frequency devices, and the support capability of the main control system for message retransmission mechanisms—these are the decisive factors, far more important than simply focusing on “whether it is wireless”.

Why do some factories experience lag during use, while others remain very stable?

The fundamental difference is not in the transmitter itself, but in the engineering implementation quality of the wireless link. For example, if no relay planning is carried out in a large steel-structure workshop, the signal may be repeatedly reflected and attenuated by multiple layers of steel plates. When the signal-to-noise ratio at the receiving end falls below -85dBm, the packet loss rate will rise significantly.

The prerequisite for stable operation is to complete a basic link budget, including matching verification of parameters such as transmit power, antenna gain, path loss, and receiver sensitivity. This step cannot be skipped, nor can it be replaced by “trying it out”.

If there are groups of frequency converters, high-power welding machines, or high-frequency heating equipment on site, their broadband electromagnetic noise may drown out the weak signals of LoRa or NB-IoT. In this case, even if the device’s nominal performance meets the standard, actual measurements may still be abnormal.

Which factory scenarios are naturally suitable for wireless pressure transmitters?

They are suitable for scenarios with high retrofit difficulty, high wiring costs, dispersed measurement points, and low requirements for data update frequency, such as retrofitting pressure monitoring points in old workshops, remote tank liquid level-pressure interlocking in tank farm areas, and outlet pressure inspection of multiple units in air compressor stations.

Typical matching characteristics include: single transmission interval ≥10 seconds, no real-time closed-loop control requirement, no strong metal shielding objects within visual range, and no continuous industrial radio-frequency interference sources nearby.

They are not recommended for interlock protection systems requiring millisecond-level response, safety instrumented systems (SIS), or the acquisition of core process parameters involved in PID control loops.

How much impact do different wireless transmission protocols have on packet loss and delay?

Protocol selection directly determines fault-tolerance capability and time determinism. LoRaWAN is suitable for low-power wide-area scenarios, but its uplink acknowledgment mechanism is weak; NB-IoT relies on cellular networks, with relatively stable latency but dependence on carrier base-station coverage; Wi-Fi 6, although offering high bandwidth, is easily affected by same-frequency interference and access quantity limitations.

Before selecting a protocol, the RSSI and SNR values at the target installation point must be measured in practice, and it must also be confirmed whether the main control system supports the data parsing interface of the corresponding protocol; otherwise, no matter how good the protocol is, it will be ineffective.

What is the key action most easily overlooked during on-site deployment?

The action most often skipped is “channel scanning and static channel locking”. Most users directly enable the default channel, but in areas with dense motor drive cabinets, the 2.4GHz band often has multiple frequency-hopping devices competing for occupancy at the same time, resulting in periodic congestion.

The correct approach is to use a spectrum analyzer or gateway equipment that supports frequency scanning before installation, record the energy distribution of each channel continuously for 24 hours, and select the channel with the lowest noise floor and the fewest fluctuations for fixed use.

In addition, “antenna polarization direction calibration” is also very easily overlooked: when the polarization planes of the transmitting and receiving antennas are inconsistent, signal attenuation can exceed 20dB, equivalent to shortening the communication distance by 90%.

If packet loss has already occurred, what should be checked first?

First check the Link Quality Indicator (LQI) and Received Signal Strength Indicator (RSSI) values in the transmitter’s local log, rather than directly suspecting device failure. LQI<150 or RSSI<-95dBm indicates that the link is already in a critical state.

Next, verify whether the air data rate (Air Data Rate) between the gateway and the transmitter is consistent. Parameter mismatch will lead to demodulation failure, appearing as “it can be received but cannot be decoded”, which is effectively the same as packet loss.

Finally, investigate whether there are issues on the main control system side such as message buffer overflow or Modbus TCP connection pool exhaustion—many so-called “wireless instability” are actually caused by upper-computer processing bottlenecks.

Checklist and action recommendations

• If there are more than three high-power frequency converters on site and the distance to the transmitter installation point is less than 5 meters, then a metal shielding enclosure must be added first and grounding treatment must be carried out; otherwise, wireless stability cannot be guaranteed.
• If the main control system only supports 4–20mA analog input, while the wireless transmitter output is a digital protocol, then an additional protocol conversion gateway needs to be configured, and this step cannot be postponed.
• If deployment is planned in a hazardous area, then it must be confirmed that the selected model has obtained the corresponding explosion-proof certification (such as Ex ib IIB T4 Gb), and uncertified products must not be put into operation online.
• If the total number of wireless nodes exceeds 200, then a clustered networking + edge computing gateway architecture should be prioritized to avoid congestion caused by all data being directly connected to the central server.
• If there is currently no support from a professional RF engineer, then it is recommended to initially conduct a pilot with only 5–10 points in non-critical process sections, and expand only after link verification is completed.

It is recommended to immediately use a handheld spectrum analyzer to conduct continuous frequency scanning for 8 hours at the intended installation location and generate a channel occupancy heat map, as this is the most reliable basis for determining whether the site has the foundation for wireless deployment.