| S.No. | Checkpoint | IS Requirement | Status |
|---|---|---|---|
| A. DB MOUNTING & ENCLOSURE | |||
| A1 | DB is mounted on non-combustible surface (concrete/tiled wall); height of main switch 1.5-2.0 m from floor Acceptance: Main switch center between 1.5-2.0 m from floor, mounted on non-combustible surface | Cl. 9.2.1 — Mounting height and location | OK NC NA HOLD |
| A2 | DB enclosure is robust, properly secured to wall, and not easily movable Acceptance: Bolts/fasteners tight, enclosure does not shift when pushed, rated for load | Cl. 9.2.2 — Mounting security | OK NC NA HOLD |
| A3 | DB enclosure is properly ventilated; air vents are unobstructed and protected from moisture Acceptance: Vents clear, no dust/debris blocking airflow, moisture guards in place if required | Cl. 9.2.3 — Ventilation | OK NC NA HOLD |
| A4 | DB door is self-closing, properly hinged, and closes completely Acceptance: Door closes securely, hinge pins tight, no gaps when closed | Cl. 9.3.1 — Access control | OK NC NA HOLD |
| A5 | Enclosure material is non-metallic or, if metallic, properly grounded (Earth resistance ≤ 0.5 Ω) Acceptance: Non-metallic enclosure; if metallic, earth bond verified with mega-ohm meter ≤ 0.5 Ω | Cl. 8.3.3 — Earth continuity | OK NC NA HOLD |
| A6 | All unused cable/connector entries are sealed or capped to prevent pest/moisture ingress Acceptance: All entry holes sealed, caps/plugs in place, no gaps visible | Cl. 9.2.4 — Sealing | OK NC NA HOLD |
| B. MAIN SWITCH & ISOLATION | |||
| B1 | Main switch/isolator is rated for load current and has visible break (break-before-make design) Acceptance: Switch rating ≥ design load current, visible 3mm break between contacts | Cl. 9.3.2 — Main switch rating | OK NC NA HOLD |
| B2 | Main switch OFF position is clearly marked (OFF = down/left as per standard) Acceptance: OFF/ON positions clearly marked, OFF position up/left when switch is in down position | Cl. 9.3.3 — Switch labeling | OK NC NA HOLD |
| B3 | Main switch is accessible and operable; mechanical lock (if fitted) functions correctly Acceptance: Switch operates smoothly, lock engages/disengages, no sticking | Cl. 9.3.4 — Operability | OK NC NA HOLD |
| B4 | Main switch is positioned before (upstream of) all protective devices (MCBs/RCBOs) Acceptance: Main switch controls all circuits, located at top/front of DB, all MCBs downstream | Cl. 9.4.1 — Circuit protection order | OK NC NA HOLD |
| C. PROTECTIVE DEVICES (MCBs/RCBOs) | |||
| C1 | All MCBs are properly sized per load current and trip current (In) matches circuit requirement Acceptance: MCB rating: In ≥ design load current, trip curve matches load type (B/C/D as required) | Cl. 9.4.2 — MCB rating | OK NC NA HOLD |
| C2 | Earth Leakage Circuit Breaker (ELCB) / RCD is fitted for final circuits with sensitivity 30 mA Acceptance: ELCB/RCD present for all final circuits, rated 30 mA, tripping threshold verified | Cl. 9.4.3 — Residual current protection | OK NC NA HOLD |
| C3 | All MCBs are firmly seated in DIN rail and latching mechanism is secure Acceptance: MCBs seated fully, no gaps, latch audible click when inserted, no movement | Cl. 9.4.4 — Device installation | OK NC NA HOLD |
| C4 | Each MCB is labeled with circuit name/reference and is clearly identified Acceptance: Labels on MCB or circuit schedule, circuit name matches design drawings | Cl. 9.4.5 — Circuit identification | OK NC NA HOLD |
| C5 | Test button on ELCB is operational; pressing TEST button trips ELCB Acceptance: TEST button press causes ELCB to trip immediately, MCB cannot be closed while tripped | Cl. 9.4.6 — ELCB function test | OK NC NA HOLD |
| C6 | Spare capacity exists in DB for future connections (minimum 20% spare MCB positions) Acceptance: Minimum 20% of MCB positions unoccupied, DIN rail has space for future expansion | Cl. 9.2.5 — Design capacity | OK NC NA HOLD |
| C7 | No double-pole protection on neutral; neutral is connected to neutral bar only Acceptance: Neutral bar separate, only single-pole MCBs on phases, neutral not switched | Cl. 9.4.7 — Neutral protection | OK NC NA HOLD |