What separates gross capacity from good motors?

Gross capacity is every cycle times the motors it holds. Uptime removes the units lost while the stand is down, and first-pass yield removes units that fail and need retest. Good motors is what the shift can pass.

How is first-pass test yield measured?

Divide motors that pass on their first test by all motors tested. Units that pass only after rework or retest sit outside the first-pass figure, which is why they count as yield loss here.

Why warn below the target instead of a fixed limit?

Because the plan is yours. The page treats your target as the limit and warns only when good motors fall below it, naming the shortfall in motors.

Does test time per motor change this result?

Indirectly. Cycles per shift already reflect the stand's pace, so if one motor family takes longer to test, lower the cycle count rather than adding a second time input.

Motors, Generators & Electrification Equipment calculator

Motor Test Stand Capacity Calculator

Estimate how many motors a test stand passes in a shift from its cycles, motors per cycle, uptime and first-pass yield. The result is compared with a target, so a shortfall shows before the shift plan is fixed.

What this calculator does

Good motors per shift from test cycle capacity, stand uptime and first-pass yield, checked against your target.

Formula used

Gross test capacity = motors per test cycle × cycles per shift
Good motors per shift = gross capacity × uptime ÷ 100 × first-pass yield ÷ 100
Uptime loss = gross capacity − run units; yield loss = run units − good motors
Capacity versus target = good motors ÷ target × 100

Inputs explained

Motors per Test Cycle: Motors the stand holds and tests in one cycle.
Available Test Cycles: Cycles the stand can complete in a shift, from its pace.
Test Stand Uptime: Share of scheduled time the stand is available to test.
First-Pass Test Yield: Motors that pass first test, as a share of units tested.
Target Good Motors: Good motors the shift plan requires; the warning limit.

How to use the result

Best suited to staffing a test stand for a shift, comparing uptime projects on one stand, checking a weekly build plan.
One shift hides mix changes; run the numbers per motor family when test times differ. First-pass yield excludes retested units, so rework capacity sits outside this figure.

Current U.S. benchmarks

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Common questions

What separates gross capacity from good motors? Gross capacity is every cycle times the motors it holds. Uptime removes the units lost while the stand is down, and first-pass yield removes units that fail and need retest. Good motors is what the shift can pass.
How is first-pass test yield measured? Divide motors that pass on their first test by all motors tested. Units that pass only after rework or retest sit outside the first-pass figure, which is why they count as yield loss here.
Why warn below the target instead of a fixed limit? Because the plan is yours. The page treats your target as the limit and warns only when good motors fall below it, naming the shortfall in motors.
Does test time per motor change this result? Indirectly. Cycles per shift already reflect the stand's pace, so if one motor family takes longer to test, lower the cycle count rather than adding a second time input.

Last reviewed 2026-10-01.