Note
How Many Technician-Days Does a Maintenance Contract Need?
Most contractors track maintenance agreements by number of sites. Twelve sites sounds manageable. What twelve sites actually represents is a block of committed technician-days distributed across the year, competing for the same team that runs your installations.
The question that matters is not how many sites you carry. It is how many technician-days those sites consume each year, which months they fall in, and whether that load fits within your available capacity before you commit to another agreement.
What Does a Maintenance Contract Actually Commit?
Every factory electrical maintenance agreement contains three types of work. Each has a different predictability.
Planned visits. These are scheduled in advance and are the most predictable part of the load. For a solar installation, planned visits typically include two panel cleans per year, one inverter inspection, and one statutory inspection. For an LED installation, one annual visit covering lux verification and connection checks is standard in the first few years. Each planned visit requires travel to and from the site plus on-site time for the technicians. Both are fixed once the agreement is signed.
Statutory inspection. Thai factories with electrical installations are required to arrange an annual inspection of their electrical systems. For sites where you hold the maintenance agreement, organizing and delivering this inspection usually falls to you. It rarely exceeds one full day for a single site, but it requires a qualified inspector and the signed report must leave the site on the day of the visit.
Emergency call-out allowance. Most agreements include a capped number of unplanned visits, typically one or two per year. Some sites will not use the allowance in a given year. A few will use it more than once. For planning purposes, count one emergency call-out per site per year as your expected load. It is distributed randomly across the calendar, which is what makes it awkward to plan around.
How Many Technician-Days Does One Site Require Each Year?
The total depends on system type and size. A worked example gives a useful reference point.
Take a 300 kWp rooftop solar installation at a factory in Samut Prakan. The maintenance agreement includes:
- Two panel cleans (April and October): 2 technicians for 2 days each = 8 technician-days
- One inverter inspection combined with the October panel clean: already covered in the 8 above
- One statutory electrical inspection in November: 2 technicians for 1 day = 2 technician-days
- Emergency call-out allowance: 1 expected call, 2 technicians for 1 day = 2 technician-days
Running total: 12 technician-days per year for this one site.
A smaller 100 kWp installation with reduced panel count runs at roughly 6 to 8 technician-days per year. A 1 MWp site with multiple inverters could reach 18 to 20 technician-days annually once cleaning crews, inspection staff, and emergency allowance are included.
For LED retrofit installations at factory scale, the annual load is lower: one planned visit and one statutory inspection on the same day, typically 2 technicians for 1 day, plus one emergency allowance visit. A typical factory LED installation commits around 4 to 5 technician-days per year.
What Does a Portfolio of Ten Sites Look Like?
Take a mixed portfolio: five solar sites averaging 12 technician-days each, and five LED sites averaging 4 technician-days each.
- Solar sites: 5 x 12 = 60 technician-days
- LED sites: 5 x 4 = 20 technician-days
- Total portfolio load: 80 technician-days per year
Spread across 250 working days, 80 technician-days looks small. The problem is that it does not spread evenly across the calendar.
Panel cleans cluster in April and October, because those months align with the seasonal schedule that works best for most factory sites. Statutory inspections cluster in the months following each site’s anniversary date. Emergency calls are random. A contractor holding twelve solar maintenance agreements may find that October alone requires 40 or more technician-days of maintenance work, which falls directly on top of the busiest installation period of the year.
The total annual number matters. The monthly distribution is what decides whether you can staff it.
How Does the Maintenance Load Change Your Installation Calendar?
A maintenance commitment is not a total annual figure in a spreadsheet. It is a series of specific weeks, partially blocked, spread across the year. Each new maintenance agreement you sign shifts your effective installation capacity downward in those weeks, whether or not you track it that way.
A contractor who has not mapped this load before quoting new installation work will, at some point, find they have oversold both. Not because they made promises they intended to break, but because the maintenance load was invisible when the installation quote was given.
The calculation is not complicated:
- List every maintenance site currently under agreement.
- For each site, list the planned visits with technician headcount, duration, and expected calendar month.
- Add one emergency call-out allowance per site (standard staffing level, no scheduled month).
- Total by calendar month.
The months with the highest totals are where your installation capacity is most constrained. In Thailand, April is already a busy period for new electrical installations at factories. If your maintenance load adds another cluster of visits in April, that month requires deliberate planning, not just the assumption that your team is available for new project work.
FAQ
When Does a Maintenance Portfolio Require Dedicated Capacity?
There is no fixed threshold. The signal is when maintenance visits regularly compete with installation start dates in the same weeks, and one side is always losing. At that point, some portion of the team is functionally maintenance-only, whether the schedule names it that way or not. Most contractors carrying more than eight or ten active solar maintenance sites reach this pressure point.
Should Subcontracted Maintenance Visits Count Against My Load?
Only if you supply some of your own staff for the visit, such as the lead technician or the qualified inspector. A fully subcontracted visit where the sub brings their own team and manages the work independently does not draw on your capacity. If you send anyone from your own team, count those days.
How Precise Does the Emergency Call-Out Estimate Need to Be?
Precise enough not to be zero. Most contractors who do not track this assume their emergency load is lower than it is, because each individual callback feels small when it happens. One expected call per site per year across ten sites is ten unplanned visits. At two technicians per visit, that is twenty technician-days distributed unpredictably across the year. That figure belongs in your capacity picture even when the exact timing is unknown.
Taking on a maintenance agreement without calculating the technician-day commitment means you are promising capacity before you know whether it is available. The TRACE 30 program builds the tools to track your maintenance load alongside the installation calendar from the day it is set up. The overview is at /program/, or book a short call at /schedule-a-call/.