Load vs capacity compares the hours of work scheduled onto a work center against the hours that work center actually has available in the same period. Load is the demand; capacity is the supply. When load exceeds capacity the station is overloaded and work spills into later periods; when load sits under capacity the station has room to spare.
EDGEBIC by User Solutions computes both sides from the same engine that builds the schedule, so the load-versus-capacity picture matches the plan exactly. This article defines the comparison and shows what it reveals.
How It Works
The two sides come from different places. Capacity is what a work center can supply in a period, derived from its shift hours, its number of machine instances, its target utilization, and any calendar effects such as holidays or downtime. A planner can override the formula for a specific day when reality differs, and that override wins. The result is the honest count of productive hours the station has.
Load is the demand: the sum of scheduled hours placed on that work center in the same period by all the jobs routed through it. The scheduler produces this directly, because it knows exactly which operations it placed where and when.
Comparing the two answers the question every planner asks: can this station actually do the work booked onto it? A station at 130 percent of capacity cannot; something must move, or capacity must grow. A station at 40 percent has slack to absorb a rush. The comparison is only as useful as its period, though, because a monthly average can smooth away a brutal single week.
A Concrete Example
Take a milling station running one day shift with two identical machines. Its capacity for the week, after target utilization and a mid-week holiday, works out to a set number of productive hours. The scheduler has booked six jobs through it that week, and their combined hours are the load.
Lay the two side by side. If the load is 87 percent of capacity, the station is busy but coping. If it is 130 percent, the plan is fiction: some of those jobs will not fit and will slide to the following week whether the schedule admits it or not. Now watch the same station burn down over time: 24 hours of booked work ahead of it Monday, 16 by Wednesday, 8 by Friday, zero by Monday. That burn-down is the load draining against capacity as the week progresses, and it shows the peak an average would have hidden.
How EDGEBIC Uses It
Load and capacity surface together in the resource calendar and the utilization report. Capacity comes from the same calculation the scheduler uses to place work, including daily overrides, so the numbers a planner reviews are the numbers the engine actually enforced. Load is the scheduled hours the engine placed. A backlog view shows remaining hours ahead of each station burning down period by period, and clicking a cell opens the detail of exactly which allocations make up the number.
That comparison is how you find your constraint. The work center whose load presses hardest against its capacity, week after week, is the bottleneck work center, and the per-job version of the same ratio is the load factor, and identifying it is the first move in the Theory of Constraints. It is also how you check a promised date honestly before you make it, rather than discovering the overload after the fact.
Load versus capacity is the raw comparison behind capacity utilization, which expresses it as a single ratio. The manufacturing glossary covers the related capacity terms, and finite vs infinite capacity scheduling explains why a plan that ignores capacity limits is a plan that lies.
Expert Q&A: Deep Dive
Q: Sales keeps promising dates my shop cannot hit. How do I show them where the wall is?
A: Put a load-versus-capacity view in front of them for the work centers in question. It lays scheduled hours next to available hours for each station and period, so an overload is visible as a bar that runs past the capacity line rather than as an argument. When one station is booked to 130 percent of its hours for the next three weeks, the conversation stops being about optimism and starts being about which orders move or where you add a shift. The comparison turns a scheduling disagreement into a shared picture of exactly which resource is the wall and by how much.
Q: One work center reads 60 percent utilized but jobs still pile up in front of it. How?
A: A period average can hide the timing. A station can be 60 percent loaded across a month yet slammed to 130 percent this week and idle the next, and the jobs pile up during the peak. Look at load versus capacity in the finest period you can, day by day if possible, rather than a monthly average. A backlog view helps here too, because it shows remaining hours burning down over time rather than a single utilization figure, so you can see the peak that the average smooths away. The pile-up is real; the 60 percent number is just too coarse to reveal it.
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