ETENWOLF S3 Cordless Tire Inflator Motor Load Current Test Report (September 2024)

Document Overview

Key Findings The ETENWOLF S3 cordless tire inflator was subjected to a motor load current draw test across two samples at pressure loads ranging from 20 PSI to 150 PSI, confirming consistent and predictable current behavior across both units. Test Date: 2024-09-06 Samples Tested: 2…

Document type

Test Report

Prepared by

Daniel Wright

Published

July 22, 2026

Last reviewed

July 22, 2026

Topics

Motor Performance

Key Findings

The ETENWOLF S3 cordless tire inflator was subjected to a motor load current draw test across two samples at pressure loads ranging from 20 PSI to 150 PSI, confirming consistent and predictable current behavior across both units.

• Test Date: 2024-09-06
• Samples Tested: 2 units (Sample #1 and Sample #2)
• Load Range: 20 PSI – 150 PSI (15 increments)
• Current Range Observed: 6.9 A – 9.7 A
• Peak Current (Sample #1): 9.7 A at 90 PSI load
• Peak Current (Sample #2): 9.5 A at 70 PSI load
• Both samples show a characteristic current rise from low load, peaking in the 70–100 PSI band, then tapering as load increases beyond 100 PSI.

Test Overview

Test Equipment & Setup

Test Procedure

1. Pre-Test: Verify the ETENWOLF S3 unit is fully charged and at ambient temperature. Record the sample identification number for each unit under test.
2. Setup: Connect the S3 inflator to a calibrated load fixture capable of holding static back-pressure at defined PSI increments. Attach a calibrated clamp ammeter or inline current meter to the motor power circuit.
3. Procedure — Sample #1: Apply a back-pressure load of 20 PSI. Allow motor to reach steady state. Record current draw in amperes. Increment load by 10 PSI and repeat through 150 PSI, recording current at each step (15 total readings).
4. Procedure — Sample #2: Repeat the identical step sequence (20 PSI through 150 PSI in 10 PSI increments) on the second unit, recording current at each load point.
5. Post-Test: Power down both units. Compare current curves across samples for consistency. Note any anomalous readings or deviations.
6. Acceptance Criteria: Both samples must exhibit a smooth, physically plausible current-vs-load profile (rising with load up to the motor’s operating range, then stabilizing or slightly decreasing as back-pressure reduces flow). No sudden discontinuities or values exceeding the motor’s rated current envelope.

Test Data & Results

Observations: Both samples show a consistent current ramp from approximately 7.0 A at 20 PSI, rising to a peak in the 70–90 PSI range (9.4–9.7 A for Sample #1; 9.5 A for Sample #2), before gradually declining toward 150 PSI. The two curves track closely, with the largest inter-sample deviation of 0.3 A occurring at 60 PSI (8.6 A vs 8.9 A) and at 150 PSI (8.7 A vs 7.7 A). This behavior is consistent with normal DC motor characteristics under increasing back-pressure. No anomalous spikes or drops were observed in either sample.

Conclusion

Document Information

Frequently Asked Questions

What current does the ETENWOLF S3 draw at maximum load?

During load current testing, the ETENWOLF S3 reached a peak current of 9.7 A (Sample #1 at 90 PSI) and 9.5 A (Sample #2 at 70 PSI). Above 90–100 PSI, current draw gradually decreases as increasing back-pressure reduces motor airflow work, which is normal DC motor behavior.

How consistent is the S3 motor performance across multiple units?

The two S3 units tested on 2024-09-06 showed closely matched current profiles across all 15 load points from 20 PSI to 150 PSI. The maximum deviation between the two samples was 1.0 A at 150 PSI (8.7 A vs 7.7 A). At most load points, the difference was 0.5 A or less, indicating strong unit-to-unit manufacturing consistency.

At what pressure does the S3 motor draw the most current?

Based on this test, peak current draw occurs in the 70–90 PSI load range for both samples. Sample #1 peaked at 9.7 A at 90 PSI, while Sample #2 peaked at 9.5 A at 70 PSI. This mid-range peak is typical for brushed DC motors used in portable tire inflators, where the motor works hardest against moderate back-pressure before flow restriction reduces effective load.

What load range was used in the S3 current test?

The test covered 15 pressure increments from 20 PSI to 150 PSI in 10 PSI steps. Both samples were tested simultaneously, with current recorded at each step. The test was conducted on 2024-09-06 as documented in source file S3负载测电流数据20240906.xls.

Related Products

Explore other ETENWOLF S3 test data and related inflation tools:

• ETENWOLF S3 Cordless Tire Inflator — Product Page
• ETENWOLF S3 Motor Load Current Test — Sheet2 Data