This page explains how to calculate the yearly cost of maintaining a machine on a fixed schedule, and compare it against the cost of only fixing it after it breaks down. This matters to a factory owner or a domestic brand's operations manager deciding how much to spend on upkeep, and to a merchandiser reviewing a maintenance proposal.
Cedar & Co., the domestic brand used in this lesson, runs its own packing and labelling equipment for its Make to Stock production, ahead of sending finished goods to its shops. Omar, its owner, has to decide how much to spend keeping that equipment running: on a fixed preventive schedule, or by waiting for it to break down.
Without this skill, an owner compares only the visible repair bill against the preventive contract's price and concludes breakdown maintenance looks almost as cheap. That comparison leaves out the value of production lost while the machine sat stopped, and it can lead a brand to under-invest in scheduled maintenance. This lesson gives you the formula-driven method that compares the two options fairly, every time.
You need: lesson 6.1's payback-period method is useful background, though this lesson can be read on its own.
By the end of this lesson you can:
Not covered here: calculating a new machine's payback period from labour and downtime saving (lesson 6.1), building the maintenance schedule that produces a preventive-maintenance total and tracking its running cost (lesson 6.3), and combining an old machine's rising maintenance cost with a new machine's payback period to decide whether to replace it (lesson 6.4).
| Term | Meaning |
|---|---|
| Preventive maintenance | Scheduled inspection and parts replacement done before a machine breaks down, on a fixed timetable. |
| Breakdown maintenance | Repair work done only after a machine has already stopped working, usually more costly than preventive maintenance. |
| Downtime cost | The value of production lost while a machine is stopped, whether for a scheduled visit or an unplanned breakdown. |
| Payback period | The time it takes for a machine's total monthly savings to add up to its total investment cost. |
| Depreciation | Spreading a machine's purchase cost over its useful working life instead of counting it all in the year it was bought. |
Preventive maintenance cost is the sum of every scheduled visit and every part replaced on a fixed timetable, calculated by formula. Breakdown maintenance cost is the sum of every emergency repair call and the downtime cost while the machine sits stopped, also calculated by formula, never typed. Comparing the two totals, never a single line item from one side against a single line item from the other, shows the real cost difference between waiting for a machine to fail and maintaining it on schedule.
*Preventive maintenance's total adds every scheduled cost component, not the visit fee alone. Parts replaced on a fixed timetable are a real, recurring cost of the preventive approach, and leaving them out understates it.*
What you meet in real life| What can differ | The shapes you meet | Why it matters |
|---|---|---|
| Comparing only the repair bill | Looking only at the emergency repair invoice and concluding breakdown maintenance is cheap, while ignoring the downtime cost of the machine sitting stopped during production hours. | This makes breakdown maintenance look artificially cheap, since lost production time is a real cost the invoice never shows. |
| Comparing full costs including downtime | Adding the downtime cost to the repair bill before comparing it against the preventive maintenance total. | Gives the true cost difference, the only basis on which to decide how much scheduled maintenance is worth. |
| A machine with a supplier service contract | An imported machine bundles its scheduled visits into one annual fee from the supplier. | The comparison method stays the same; the preventive side is simply already summed for you in the contract price. |
| A machine near the end of its useful life | As a machine ages, breakdown frequency, and so breakdown cost, tends to rise even if the preventive schedule stays the same. | The comparison should be redone periodically, not calculated once and trusted forever. |
| A domestic Make to Stock brand's own equipment | Cedar & Co. maintains its own packing and labelling equipment for stock it produces to its own forecast, not to a single order's deadline. | The comparison method does not depend on market or business model; only how urgently a stoppage disrupts a specific delivery date differs. |
| An export factory's shared equipment | Delta Garments maintains equipment shared across several export orders, where a breakdown risks missing more than one buyer's delivery date at once. | The same formula applies, but the cost of a breakdown's downtime can be higher when several orders depend on the same machine. |
Cedar & Co. runs its own packing and labelling equipment ahead of sending Make to Stock goods to its 12 shops. Omar, its owner, is reviewing an illustrative maintenance comparison for this equipment, framed here as a clearly illustrative teaching example, not a fixed brand fact: preventive maintenance costs USD 240 (illustrative) a year in scheduled visits plus USD 160 (illustrative) a year in parts replaced on schedule. Breakdown maintenance costs USD 420 (illustrative) a year in emergency repair calls plus USD 610 (illustrative) a year in downtime cost while the equipment sat stopped. Omar has to decide whether the preventive schedule is worth its price.
Using the workbook's own formulas, the preventive total sums scheduled visits and parts replaced, the breakdown total sums repair calls and downtime cost, and the difference subtracts one total from the other.
A common mistake is looking at an emergency repair invoice, seeing it costs only slightly more than the preventive contract's total, and concluding the two options cost about the same. This makes breakdown maintenance look artificially cheap, because the value of lost production time while the machine sat stopped was never counted, and it can lead a factory or brand to under-invest in scheduled maintenance and accept more unplanned stoppages than the true cost comparison justifies.
This lesson compares two ways of keeping a machine running: fixing small things on a schedule before they become big problems, or waiting until something breaks and fixing it then. Add up everything the scheduled approach costs: the visits, and any parts replaced. Add up everything the wait-and-fix approach costs: the repair calls, and the value of all the production lost while the machine sat still. Comparing only the repair bill against the scheduled cost hides the real difference, because the repair bill never shows what was lost while the machine was not working. Once you add that lost time in, waiting for a breakdown is usually the more expensive choice, sometimes by a wide margin.
Omar, the owner of Cedar & Co., is reviewing an illustrative maintenance proposal for the brand's own packing equipment.
The two figures side by side, as Omar first sees them:
Is comparing the repair-call cost alone against the preventive total a fair comparison? Decide before opening the answer.
No. The repair-call cost alone leaves out the downtime cost, and that omission hides the real difference.
First fact. The repair-call cost alone, USD 420 (illustrative), does not include the USD 610 (illustrative) downtime cost of the equipment sitting stopped while it was fixed.
Second fact. The fair comparison is breakdown maintenance's full total (420 + 610 = USD 1,030, illustrative) against preventive maintenance's full total (USD 400, illustrative).
That is a difference of USD 630 (illustrative) a year, not the roughly USD 20 difference the repair-call-only comparison would suggest. Omar's brand would be underestimating the real cost of breakdown maintenance by more than thirty times if he stopped at the repair invoice alone.
Framed qualitatively, since the specific dollar figures in this course are illustrative teaching numbers, not fixed facts: comparing only the repair invoice while ignoring downtime cost can make breakdown maintenance look nearly as cheap as preventive maintenance, when in reality the full cost, once lost production time is included, is substantially higher. A domestic brand or export factory that makes this comparison mistake can under-invest in scheduled maintenance and accept far more unplanned stoppages than the true cost comparison would ever support, paying the difference in repeated downtime rather than in one predictable, scheduled cost.
Open the Machine investment payback calculator and go to its "Maintenance cost" sheet. The illustrative example column already shows scheduled visits USD 240, parts replaced USD 160, emergency repair calls USD 420, and downtime cost USD 610, with both totals and their difference calculated by formula. In the "Your machine" columns, enter your own equipment's four figures, and the sheet calculates your own comparison the same way. Download link: `templates/T08-C06-machine-investment-payback-calculator.xlsx`.
1. Why must downtime cost be included in the breakdown maintenance total, not just the repair-call cost?
2. In the illustrative example, what is the difference between breakdown maintenance total (USD 1,030) and preventive maintenance total (USD 400)?
3. What typically happens to a machine's breakdown-maintenance cost as it gets older, even if its preventive schedule stays the same?
| EN | AR | FR | TR | Meaning |
|---|---|---|---|---|
| Payback period | فترة استرداد الاستثمار | Délai de récupération | Geri ödeme süresi | The time it takes for a machine's total monthly savings to add up to its total investment cost. |
| Preventive maintenance | الصيانة الوقائية | Maintenance préventive | Önleyici bakım | Scheduled inspection and parts replacement done before a machine breaks down, on a fixed timetable. |
| Breakdown maintenance | صيانة العطل | Maintenance corrective | Arıza bakımı | Repair work done only after a machine has already stopped working, usually more costly than preventive maintenance. |
| Downtime cost | تكلفة وقت التوقف | Coût des temps d'arrêt | Duruş maliyeti | The value of production lost while a machine is stopped, whether for a scheduled visit or an unplanned breakdown. |
| Depreciation | الإهلاك | Amortissement | Amortisman | Spreading a machine's purchase cost over its useful working life instead of counting it all in the year it was bought. |
You now know how to compare preventive and breakdown maintenance cost for a machine you already own. The next lesson builds the schedule behind that preventive-maintenance figure, showing exactly which tasks and intervals produce it, and how to track whether the schedule is actually being followed. Back to the course map