An open-space wireless range is not a cabinet-layout design. For switchgear temperature monitoring, document measuring points, partitions and receiver placement, then evaluate representative cabinet states and the receiver-to-host data path. Keep reception failure and stale-data handling in the acceptance record, not just the temperatures that arrived.
- W-S01, open space
- Up to 180 m
- W-S01, inside a cabinet
- 60 m
12 sensor points Listed capacity of W-D21; point count and radio reach are separate constraints.
Values from W-S01 and W-D21. Compare their conditions; test the actual closed-cabinet arrangement.
Read the two range statements without combining them
The W-S01 entry lists ≤ 180 m in open space; 60 m inside a cabinet. The W-D21 entry separately lists ≤ 60 m wireless range. These are manufacturer-stated product figures with different stated contexts, not distances demonstrated in your arrangement.
Draw the relevant cabinet boundaries and compartments, measuring points, receiver and host connection. Distance alone leaves out the material and arrangement between the devices.
Prepare a cabinet-state matrix
| Scenario to agree with the equipment team | Configuration to record | Observations to keep |
|---|---|---|
| Initial reference arrangement | Sensor identities, point positions, receiver/antenna position | Which points report and how observations are timestamped |
| Intended installed arrangement | Required doors/panels/partitions and operating state | Missing, delayed or restored readings |
| Permitted service/configuration change | The actual change and responsible party | Whether the earlier observations still apply |
| Input or communications interruption | Agreed test boundary and expected host response | Recovery, stale values and unavailable-data indication |
The matrix defines questions, not instructions to alter energized switchgear. Select permissible states and work methods with the parties responsible for the equipment. An open-door demonstration should not be substituted for the intended installed arrangement.
Separate radio, serial link and application data
The receiver’s 12-point capacity is a different constraint from its radio reach. Its RS485 Modbus-RTU listing adds another interface to review.
Modbus over Serial Line distinguishes protocol/serial behaviour and physical interfaces. The application protocol specification describes the request/reply and data model. Neither document supplies the W-D21’s proprietary register mapping.
Request serial settings, addressing, supported functions, register definitions, scaling and any status information for the selected receiver revision. Do not assign a register address or polling interval from a generic example.
Decide how the host treats old data
Ask whether the receiver exposes measurement time, age, validity or diagnostics; the catalogue summary does not establish them. Agree on how the host distinguishes a current measurement, a retained value and an unavailable point.
That decision belongs in the system acceptance record along with the alarm owner. A received temperature is not evidence of a complete protection or fault-detection function.
Close the evidence record
Keep the layout, model/firmware revisions, current conditions, observation period, matrix states, logs and unresolved questions together. If a partition, mounting point or configuration changes, identify which observations need repeating.
Use the minimum-current worksheet for sensor power and the switchgear application brief for the component and responsibility handoff.
Sources & method
This is a planning matrix based on the linked product summaries and public Modbus specifications. It is not a completed radio survey, a proprietary register map or an installation/safety procedure.