Chamber Specification Builder
Answer six questions about your DUT, test standard, and programme. The builder calculates the minimum chamber specification — temperature range, cooling capacity, humidity, workspace volume, and controller requirements — ready to attach to an RFQ.
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Chamber Specification Builder
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Step 1 of 6
Tell us about your DUT
The DUT's thermal mass determines the cooling power required — and whether a benchtop chamber can run your test or a floor-standing unit is needed.
Include the fixture, brackets, and cables — everything inside the workspace that the chamber must thermally cycle.
Determines specific heat capacity. If mixed, choose the dominant material by mass.
Used to estimate minimum workspace volume with 100 mm clearance on all sides.
Power dissipated by the DUT during test. Zero if unpowered or unknown.
Step 2 of 6
Test standard and method
The standard determines the chamber type required. Some substitutions — such as thermal shock for temperature cycling — are explicitly prohibited.
Step 3 of 6
Test conditions
The temperature extremes and ramp rate from your test plan or standard. These determine cooling and heating capacity requirements.
Air ramp rate from the standard or test plan. The builder will calculate the loaded rate for your DUT.
Minimum time at T-low and T-high per cycle from the standard.
Humidity control is only possible within a sub-range of the full temperature range. Enter the range where humidity must be controlled.
Step 4 of 6
Programme scope
Number of cycles, samples, and concurrent chambers affects the total test duration and capacity planning.
Requires: calibrated chamber, documented IQ/OQ, traceable thermocouple on DUT
Step 5 of 6
Facility conditions
Chamber performance degrades at higher ambient temperatures. Facility power and floor load determine what can be installed.
Use the highest summer temperature in your lab — not the nominal. Cold-end performance is typically 5–10°C worse at 30°C vs 23°C.
Floor-standing chambers can weigh 400–800 kg. Walk-in chambers may exceed 2,000 kg. If unknown, enter 500.
Required for humidity chambers (deionised) and some high-capacity compressor cooling systems.
How the specification is calculated
Required cooling power is calculated as P = m × Cp × (dT/dt) for the DUT load, plus the chamber's baseline load at T-low (estimated at 30–35% of rated capacity at 0°C). The minimum workspace volume adds 100 mm clearance on all sides of the DUT envelope — the minimum for adequate airflow per most manufacturer guidelines.
Ambient temperature penalty is applied as approximately −1.5°C cold-end performance per °C above 23°C reference. Self-heating DUT power is subtracted from available cooling capacity.
Standards with specific chamber type prohibitions (JESD22-A104 NOTE 2, IEC 60068-2-14 Na vs Nb) are flagged where relevant. The specification is a minimum requirement — add margin based on programme risk and expected chamber age.
Related: How to Choose an Environmental Test Chamber · Loaded Ramp Rate Calculator · JESD22 Standards Guide