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Field Testing & Twin SaaS
🇬🇧 Full UI + PDF + National Standard Mapping: UI + PDF in English. Normative references follow international IEC 60364, BS 7671:2018+A2:2022, IEEE, and NFPA 70E/70B.
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#24EPO (Emergency Power Off) Functional Safety Checklist

Project Framework (report reference): IEC 60364-4-41Applicable Standard: ANSI/TIA-942 / NEC 645.10
Module Field Guides, Standard Selection & Tutorials (3)Browse All 93+ Guides →
1 · Field Measurement ProcedureHow to Measure & Test EPO Functional Safety on Site: Step-by-Step Field Procedure (ANSI/TIA-942 / NEC 645.10)2 · Standards & Limit TablesWhich Standard Applies to EPO Functional Safety? Acceptance Limits, Annex Tables & Regional Equivalents (ANSI/TIA-942 / NEC 645.10)3 · OhmCert Tutorial & Case StudyHow to Complete a EPO Functional Safety Certificate in OhmCert: Worked Case Study & Troubleshooting

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-EPO0-D9CF
Plant & SLD (Auto-SLD)

Standard Limits, Equations & Space Presets

NEC Article 645.10, NFPA 75, and ANSI/TIA-942 Emergency Power Off functional verification: exit coverage, < 500 ms end-to-end disconnection, IEC 60947-2 shunt trip voltage window (85%-110%), and NFPA 72 loop supervision.

One-Click Normative Presets (Auto-fills Target Limits)

Measured Inputs

Calculated / Evaluated Results

NEC Article 645.10 requires an EPO at each principal exit that de-energises all IT power and disconnects battery systems, with a protected actuator and manual reset. The timings below are functional verification criteria, not code limits.

Pending / Not tested — results stay neutral until valid measured values are entered.

  • EPO Station Coverage

    -

    Not tested - enter the measured value. Acceptance: An EPO station at each principal exit door of the IT / electrical equipment room [NEC 645.10 / NFPA 75]

    Pending

  • De-energisation Time

    - ms

    Not tested - enter the measured value. Acceptance: Immediate disconnection on actuation, verified end to end within 500 ms [NEC 645.10 functional test]

    Pending

  • Shunt Trip Coil Supply Window

    -

    Not tested - enter the measured value. Acceptance: 85% <= V_coil <= 110% of rated coil voltage (IEC 60947-2 §7.2.1.4 operating window: 70%-110%) [IEC 60947-2 §7.2.1.4 / OEM data]

    Pending

  • Interlock Loop Integrity

    - Ohm

    Not tested - enter the measured value. Acceptance: Monitored loop within the supervision window; an open loop must raise an alarm [NFPA 72 supervision requirement]

    Pending

Verification Checklist (0 / 13)

Pending

  • 1EPO pushbuttons installed at every principal exit door of the data / UPS room [NEC 645.10]

  • 2Hinged transparent molly-guard covers with local buzzer fitted to prevent accidental actuation

  • 3Cause-and-Effect interlock matrix verified for all UPS modules, battery breakers, PDUs, and STS units

  • 4HVAC / CRAC fire dampers and underfloor airflow interlocked to close on EPO actuation [NFPA 75]

  • 5Shunt trip and Under-Voltage Release (UVR) coils verified across all affected main breakers

  • 6Monitored loop wire-break / short-circuit supervision fault alarm proven at BMS/FACP [NFPA 72]

  • 7Dedicated battery-backed 24 V DC / 110 V DC EPO control power supply verified independent of utility

  • 8Manual key-switch reset verified: resetting EPO pushbutton does NOT automatically re-energise buses

  • 9Clean-agent gas suppression (FM-200 / Novec 1230) pre-discharge and discharge interlocks verified

  • 10Emergency egress lighting and fire alarm circuits confirmed EXEMPT from EPO trip (remain energised)

  • 11Integrated dry-run / dummy breaker witness test completed under approved Method of Statement (MoS)

  • 12EPO station signage high-contrast, unobstructed and bilingual where required

  • 13Operations & security staff trained on emergency actuation authority and recovery sequence

General Notes

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Free plan: 5 of 5 inspections / calculations left this month.