#17Data Center ATS / STS Fast Transfer Test Report
Multi-Asset / Multi-Point Equipment Schedule
Inspect multiple transformers, panels, rooms, motors, or RCDs in this module without overwriting previous assets. Each item receives a permanent QR Sticker UID preserved across annual audits.
Sticker UID: OC-ATS0-A8E1Standard Limits, Equations & Space Presets
IEEE 3008, ANSI/TIA-942, and ITIC (CBEMA) power acceptability curve limits for Static Transfer Switches (STS <= 1/4 cycle) and Closed/Open Transition Automatic Transfer Switches (ATS).
Measured Inputs
Calculated / Evaluated Results
A static transfer switch must complete the transfer inside a quarter cycle so the load stays within the ITIC ride-through envelope; an engine-generator EPSS must accept load within 10 s for a Type 10 system (NFPA 110).
Pending / Not tested — results stay neutral until valid measured values are entered.
- Pending
Transfer Time
- ms
Not tested - enter the measured value. Acceptance: Transfer completed within a quarter cycle (5.00 ms at 50 Hz) [IEEE 3008 / ANSI-TIA-942 / OEM specification]
- Pending
Phase Synchronisation
- deg
Not tested - enter the measured value. Acceptance: Sources in synchronism within 10 degrees before transfer [IEEE 3008 practice]
- Pending
Voltage Dip vs ITIC Envelope
-
Not tested - enter the measured value. Acceptance: ITIC: up to 100% dip for <= 20 ms, <= 30% dip up to 500 ms, <= 20% dip beyond 500 ms [ITIC (CBEMA) curve, referenced by IEEE 1100]
- Pending
Retransfer Time
- ms
Retransfer must be equally bumpless and is normally delayed until the preferred source is stable.
- Pending
Test Load Representativeness
- %
Not tested - enter the measured value. Acceptance: Test at >= 30% of design load for a representative result [Commissioning convention]
Verification Checklist (0 / 16)
1Preferred Source (Source 1) and Alternate Source (Source 2) voltage, frequency, and phase sequence (L1-L2-L3 clockwise) verified identical
2ATS / STS continuous current rating and short-circuit withstand/closing rating (Icw / WCR) verified against upstream protective device [UL 1008 / IEC 60947-6-1]
3Synchronism-check relay (ANSI 25) phase angle window (<= 10 deg), delta-V, and delta-f limits verified prior to transfer
4High-speed power quality / oscilloscope waveform capture connected across load bus to record exact transfer gap and voltage dip
5Static Transfer Switch (STS) SCR transfer verified within <= 1/4 cycle (<= 5.0 ms at 50 Hz / <= 4.17 ms at 60 Hz) [IEEE 3008]
6Closed-transition ATS make-before-break parallel overlap verified <= 100 ms with anti-paralleling protection timer active
7Open-transition ATS / EPSS start-to-accept-load time verified <= 10 s for NFPA 110 Type 10 life-safety/critical branches
8Load bus voltage transient during transfer verified inside the ITIC (CBEMA) ride-through envelope with zero server PSU dropouts
9Time-delay settings verified: Engine Start Delay (TDES), Normal-to-Emergency (TDNE), Emergency-to-Normal Retransfer (TDEN), and Engine Cool-down (TDEC)
10Neutral switching topology verified: 4-pole overlapping neutral or 3-pole solid neutral matches earthing/GFP design [IEEE 3008]
11Mechanical and electrical interlocks proven to prevent unintended out-of-phase paralleling of unsynchronised sources
12STS thyristor (SCR) gate-drive health, redundant power supplies, and cooling fan diagnostics clear of faults
13Make-before-break Maintenance Bypass / Isolation switch sequence tested without load interruption
14Infrared thermography and torque verification completed on Source 1, Source 2, and Load busbar terminations
15BMS / DCIM / EPMS status telemetry (Source 1 Available, Source 2 Available, Switch Position, Bypass Active, Transfer Inhibited) verified
16Test conducted at representative load (>= 30% rated) under approved Method of Procedure (MOP) and signed off
General Notes
Free plan: 5 of 5 inspections / calculations left this month.