The W-S01 listing specifies CT induction with load current greater than 3 A. Check that condition at the actual proposed measuring point, including the lowest-current states when readings are needed. A cabinet nameplate current or a nearby energized conductor does not establish that the selected sensor will have operating power.
CT induction, load current > 3 A
| Equipment state | Question at the measuring point |
|---|---|
| Standby or idle | Is enough load current present when a reading is required? |
| Normal operation | What is the lowest expected current, including intermittent loads? |
| Loss and recovery | How does this revision report unavailable and restored data? |
The sensor's power condition is one selection input. These questions are not a record of a ModuWeave test.
A current rating and an operating current are different inputs
A CT-powered sensor obtains operating energy from the conductor. For W-S01, the published condition is load current > 3 A. Do not generalize that threshold to every CT-powered sensor, or replace it with the equipment’s maximum rated current.
The important question is whether the point meets the applicable condition when the project needs a reading. A high normal current does not answer the question for standby, intermittent operation or an unloaded state.
Fill in the operating-state worksheet
| Equipment state | Current at this point | Is a reading required then? | What remains to establish? |
|---|---|---|---|
| Normal operation | Record the relevant measured/confirmed range | Define the requirement | Selected model’s power condition |
| Minimum-load operation | Do not substitute the nameplate rating | Define the requirement | Availability at the lowest relevant load |
| Standby or unloaded | Record the actual state | Define the requirement | Whether another power method is needed |
| Return to load | Record the transition to evaluate | Define the requirement | Reporting and recovery behaviour for the revision |
“Unknown” is an acceptable first entry. It becomes a measurement or documentation task before the sample configuration is accepted. Do not fill the gaps with an assumed energy reserve or recovery time.
Ask what the receiver can distinguish
Temperature, measurement time and reception time are not the same value. Ask what timestamps, device states or diagnostics the exact sensor/receiver system exposes. The published catalogue summary does not establish those features.
The W-D21 receiver is a candidate data interface, with 12 listed points and RS485 Modbus-RTU. Confirm supported sensor revisions and the applicable map. The host team must decide how a missing or old value is represented rather than silently treating the last number as current.
Keep mounting review separate from power review
W-S01 is listed for strap mounting and has a stated mechanical envelope. That identifies a product form; it is not permission to install it in energized equipment or a substitute for an equipment-specific work method.
Describe the conductor/joint, available space, mounting constraints and permitted installation window. Isolation, clearances and site procedures remain with the qualified parties responsible for the electrical equipment.
What should a sample review establish?
Keep the sensor and receiver revisions, measuring point, current states, required data availability and observations in one record. Use an agreed reference method for temperature comparison and record where readings are missing or restored.
For cabinet reception and host mapping, continue with the metal-cabinet wireless checklist. For the full project handoff, use wireless temperature monitoring for switchgear. The answer may be a different power method or an unresolved question, not an immediate order.
Sources & method
The threshold is specific to the linked manufacturer-stated W-S01 configuration. The worksheet identifies questions to resolve; it is not a measured startup/dropout curve or an electrical installation procedure.