AC1 vs AC3 ratings describe different contactor duties. AC1 concerns non-inductive or slightly inductive loads. AC3 concerns squirrel-cage motor duty, including starting and switching off during normal running. Read the category with the stated operating voltage and current.
For an aluminum cutting-machine proposal, keep the actual contactor reference and the equipment documentation together. A current figure copied without its category leaves the electrical reviewer with an incomplete comparison.
Four records make the comparison readable
- The load and its place in the machine.
- The intended switching duty.
- The category, voltage and current recorded together.
- The exact component reference and approved configuration.
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AC1 vs AC3 ratings: begin with the stated duty
Schneider Electric’s AC1 and AC3 explanation distinguishes resistive or slightly inductive load duty from squirrel-cage motors switched off while running. Its TeSys explanation connects utilization categories to both the load and the operating cycle.
The TeSys Giga category table also lists AC4 separately for squirrel-cage motor starting, plugging and inching. This is a reason to preserve the actual switching description when requesting an electrical review.
Use the labels to understand the proposal. The responsible electrical professional still needs the actual component documentation and machine arrangement to determine suitability.
These categories do not identify a saw motor’s output, a complete machine’s supply requirement or its accepted cutting rate. Keep those records under their own headings.
Check 1: identify the actual load being controlled
Name the component or assembly served by the contactor in the equipment documents. A general description such as “machine electrical parts” does not show which circuit the entry belongs to.
Connect the component reference to the controlled drawing and parts list. If the proposal includes several motors or accessories, preserve their separate identities rather than combining them under one current figure.
Request the load information required by the responsible reviewer. Keep its source visible, including the applicable motor or equipment documentation and revision.
The saw power-supply guide addresses the complete equipment and site interface. Refer to that review when a component entry is being interpreted within the larger ordered configuration.
Keep optional equipment identifiable. A contactor listed for one accessory does not automatically describe every powered item in the package.
Check 2: describe the intended switching sequence
State what the machine is expected to do during the reviewed operating sequence. Give the supplier the actual production description and ask the electrical reviewer to identify the applicable duty.
If the proposal includes repeated starts, reversing or positioning actions, preserve the details requested for that review. Avoid replacing the sequence with a broad label such as automatic operation.
Identify which component performs each function in the approved control arrangement. A motion observed at the machine does not by itself explain which contactor or drive is responsible.
Keep the motor duty record separate from the contactor category. Our motor duty-cycle guide discusses the motor’s operating pattern. Here, the question concerns the switching device entry in the electrical documentation.
When the proposed control arrangement changes, ask whether the earlier component review still applies. Preserve the revised drawing and the response with the quotation.
Check 3: retain category, voltage and current in one entry
Read the appropriate field in the identified component data sheet. Keep its category label, operating voltage and rated current together with the conditions attached to that entry.
A larger current number in another category is a different entry. Ask the reviewer to explain the applicable rating rather than silently substituting the larger number into the procurement summary.
Preserve units and headings when copying data into a comparison table. A column called only “capacity” can obscure whether the original entry concerned current, power or another characteristic.
If the sheet also gives motor power values at several voltages, retain the applicable heading and scope. Do not turn one value into a universal machine rating.
| Data-sheet field | Question for the reviewer |
|---|---|
| Category | Which stated duty does this entry describe? |
| Operating voltage | Which voltage belongs to the copied rating? |
| Rated current | What category and conditions accompany this number? |
| Document reference | Which exact component and revision does the entry cover? |
Check 4: keep the complete component reference
Retain the full offered part reference, including the suffix information required to identify the actual version. Keep the supplier’s data sheet with that reference.
If a proposed substitute has a similar name or a familiar manufacturer, request its own document review. Brand recognition and enclosure appearance do not settle the equivalence question.
Keep control-side requirements under their own headings in the component record. Ask the responsible reviewer to verify them from the actual documentation instead of inferring them from a main-contact rating.
Identify who approves a proposed component change and where that conclusion is recorded. A purchasing summary should show the approved reference and any unresolved condition.
For an existing machine, preserve its identity and applicable electrical drawing revision. A parts list from another configuration may provide useful context but needs an explicit applicability review.
A fictional quotation gap: two current entries with missing labels
Imagine machine proposal Q71, revision C. Offer A retains a contactor reference, category, operating voltage and current entry. Offer B lists a current figure under “contactor capacity” but omits its category and voltage.
The figures cannot yet be compared as equivalent procurement entries. Ask Offer B’s supplier to provide the component data sheet and identify the applicable row for the proposed duty.
Please retain the full contactor reference for proposal Q71. Identify the rating category, operating voltage and current entry used in the electrical review, together with the applicable drawing revision and switching description.
Keep the original offer while requesting that clarification. Correcting a summary should leave the supplier’s stated information traceable.
This fictional example gives no recommended contactor size, actual machine rating or approved component substitution. It shows how a missing heading creates a document comparison problem.
Prepare a clear handover before accepting a change
Bring the machine identity, ordered configuration, component list and applicable electrical drawings together. Keep supplier responses beside the questions they resolve.
Have the responsible electrical personnel review the actual arrangement and proposed changes. Installation and servicing follow the applicable equipment documentation.
For a cutting-machine discussion, include the aluminum section, required cut pieces and expected operating sequence. This helps connect the equipment proposal to the real purchasing brief.
Send JiurunCut the cutting requirements and configuration questions. Keep AC1 vs AC3 ratings in the electrical document package with their complete labels and references.
Quick purchasing questions
Can I compare two current figures without their categories?
Request the original rating entries and the intended duty before treating them as equivalent.
Does a category establish a motor’s output?
Keep the motor output record and contactor rating record separately identified.
Does a similar part name approve a replacement?
Retain the exact proposed reference and obtain the applicable component and machine review.