Pricing and Varying a Four-Way Motor Control Panel
A small panel-building firm quotes for a 4-way motor control panel for a rice mill: one 63 A 4-pole MCCB incomer, three DOL feeders for 2.2 kW motors (9 A contactors, 4–6 A thermal relays, start/stop push buttons, run lamps), and one blank spare bay. The quoted rates are: CRCA sheet 2 mm, 3.0 m² at ₹700/m²; powder coating 3.0 m² at ₹250/m²; MCCB ₹2,400; contactors ₹850 each; relays ₹700 each; push-button sets ₹180 each; lamps ₹120 each; wire, lugs, busbar and terminals ₹1,800; glands and miscellaneous ₹450. Wastage is allowed at 5 % on sheet and wire only. Fabrication takes 8 h at ₹180/h, wiring 10 h at ₹150/h and testing 2 h at ₹150/h. Overhead is 8 % of direct cost and profit 12 % on the overhead-inclusive cost; GST is 18 %. The customer's budget is ₹25,000 including GST.
1. Build the price and decide whether the order can be accepted within the customer's budget.
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| Item | Calculation | ₹ |
|---|---|---|
| Sheet 2 mm | 3.0 × 700 | 2,100 |
| Powder coating | 3.0 × 250 | 750 |
| MCCB 63 A 4P | 1 × 2,400 | 2,400 |
| Contactors | 3 × 850 | 2,550 |
| Thermal relays | 3 × 700 | 2,100 |
| Push-button sets | 3 × 180 | 540 |
| Lamps | 3 × 120 | 360 |
| Wire, lugs, busbar, terminals | - | 1,800 |
| Glands, misc. | - | 450 |
| Material subtotal | 13,050 | |
| Wastage | 5 % of 2,100 + 5 % of 1,800 | 195 |
| Material incl. wastage | 13,245 | |
| Labour | 8×180 + 10×150 + 2×150 | 3,240 |
| Direct cost | 16,485 | |
| Overhead 8 % | 0.08 × 16,485 | 1,318.80 |
| Cost before profit | 17,803.80 | |
| Profit 12 % | 0.12 × 17,803.80 | 2,136.46 |
| Price before GST | 19,940.26 | |
| GST 18 % | 0.18 × 19,940.26 | 3,589.25 |
| Quoted price | 23,529.51 ≈ 23,530 |
Against a ₹25,000 budget the quote leaves ₹1,470 (5.9 % of the budget) as headroom. Accept the order, but state a quotation validity of about 15 days because copper and sheet prices move, and specify the make and rating of the MCCB and contactors so a cheaper substitute is not assumed later.
2. The customer now wants the spare bay fitted as a fourth DOL feeder but will not pay more than ₹25,000. What do you do?
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Cost the addition honestly:
- Extra material: contactor 850 + relay 700 + push-button set 180 + lamp 120 + wire/lugs 150 = ₹2,000; wastage 5 % on wire = ₹7.50 → ₹2,007.50.
- Extra labour: 2 h wiring/commissioning × ₹150 = ₹300.
- Extra direct cost = ₹2,307.50.
- With 8 % overhead (₹184.60) and 12 % profit (₹299.05): ₹2,791.15 before GST; with 18 % GST: ₹3,293.56.
- New price = 23,529.51 + 3,293.56 ≈ ₹26,823.
To hold ₹25,000 including GST, the pre-GST price can only be ₹25,000/1.18 = ₹21,186. Against an overhead-inclusive cost of 18,792.50 × 1.08 = ₹20,295.90, that leaves about ₹890 profit - roughly 4.4 % on cost instead of 12 %. That removes the buffer for wastage and rework and is not a decision to make informally.
Recommended action: issue a written variation at about ₹26,800 for the fourth feeder, or hold ₹25,000 only by deleting a defined scope item with the customer's signature. Never absorb the extra silently; it teaches the customer that quoted prices are negotiable after the order.
3. What maintenance schedule and spares would you hand over with this panel?
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Handover pack:
- Drawings: single-line diagram, terminal numbering, relay settings, cable schedule.
- Test sheets: insulation resistance at 500 V (record actual value), earth continuity, phase sequence, contactor pick-up/drop-out, relay trip test.
Maintenance schedule:
- Monthly: visual check for dust, smell and discoloured terminals; check door gasket and fan filter; confirm lamps and push buttons.
- Every 6 months: torque all power terminals to the manufacturer's value; inspect contactor tips and arc chutes; clean; confirm the relay dial is still at the set value and has not drifted.
- Annually: insulation resistance test, thermographic scan under load, relay injection test, earth resistance test.
- Every 2,000 operations or on pitting: replace contactor tips or the contactor.
Spares to stock: one contactor, one thermal relay, one push-button set, one lamp, fuses and terminal blocks.
A log card should record every trip with its current and cause. A repeated trip is data, not a nuisance.