Electrical Bill of Material Selection for DOL & Star Delta

Explore how the electrical bom for switchboards is developed from tender inputs through estimation and engineering to drawing approvals, with iterative revisions before manufacturing in dol and star delta configurations.

Configure a motor feeder BoM by selecting components rated for the load current and feeder type, considering power factor and dual-type and star-delta variations.

Create a feeder list from the single-line diagram by identifying two incoming feeders with 800 A ACB, interlock, voltmeter and ammeter, and outgoing feeder codes on a 415 V bus.

Analyze withdrawable motor feeder types such as M1.3, M1.6, M1.7, and P1.2, featuring SFU, on-off lamps, VFDs, and feeder ratings, including spare and dual/reversible configurations.

Prepare the feeder list for SLD-1 by detailing outgoing feeders, incoming feeders, and control transformer feeders with quantities, kVA and kilowatt ratings.

Derive a feeder list from an sld of a mc1 switchboard with 95 feeders, incoming main bus 1250a at 415v 50 Hz three-phase, and aluminium xlpe cabling.

Explore the feeder list from the SLD, covering unique feeder types like dual motor and star-delta, with emphasis on incomers, MCBs, control transformers, and burden calculation to come.

Decide the make of components for the bill of materials using price lists from approved OEMs, then select the lowest bid meeting switchboard feeder requirements.

Understand selecting motor feeder components with a type two coordination chart to protect against short circuits and overloads, using circuit breakers, contactors, and bimetal overload relays.

Explore type two coordination charts for motor starters, including MPCB and MCB selections for star-delta and dual feeders, with emphasis on overload protection, fuse-less options, and normal starting criteria.

Configure a 7.5 kW dual starter feeder BOM using Siemens fuse selection, detailing an MPCB with built-in overload protection, PCB switching device, power contactor, and start-stop pushbutton with indicating lamps.

Configure the 7.5 kw dol motor outgoing feeder with the 32027 power contactor, 32 a at 415 v, featuring one no and one nc auxiliary contact.

Configure the bom for a 7.5 kW dol motor outgoing feeder by selecting a 0–20 ampere ammeter with a 20:1 ct and suppressed-scale metering to monitor 15.5 a full-load current.

Select green start and red stop momentary push buttons with rear auxiliary contacts for a 7.5 kW DOL motor feeder, and choose red, green, and amber 240 volt AC lamps.

Calculate the 240-volt ac control burden (81 v closing, 10.5 v holding, two led lamps totaling 82 va) and choose a 6 a mcb, min 0.5 a, catalog 542067 rc.

Configure the BoM for a 75 kW star-delta feeder with main, delta, and star contactors, a bimetal overload, and a star-delta timer.

Select 115 A 31054 contactors for line and delta, 65 A 32037 for star, configure plus two NC auxiliary blocks with 230 V AC coil for the 75 kW feeder.

Configure the 75 kilowatt star-delta starter with a thermal overload relay, class ten, frame six, for independent or contactor mounting, with a 70–100 A setting and mechanical reset options.

Configure the bom for a 75 kW star-delta motor outgoing feeder, detailing the star-delta timer 315, instantaneous and delayed contacts, ammeter selector, CTs, and inrush current.

Configure the bom for a 75 kW star-delta feeder by selecting push buttons, indicating lamps, and a six ampere double-pole mcp (542067 RC) to satisfy control loads.

Learn how to generate the control supply for switchboards by performing burden calculations for control circuitry and understanding tap options from incoming or outgoing sides.

Determine the VA burden by adding the closed burden of all outgoing feeders to the closing burden of the highest rated motor feeder, plus 20-25% spare capacity.

Calculate the control transformer VA rating by summing PA contactor burdens in motor feeders, using datasheet values for closed and closing burdens of star delta and main contactors.

Use a Siemens pa contactor template in Excel to speed DOL and star-delta data extraction, include a yellow column, and size control transformers feeding bus sections A and B.