What the chart is actually saying
A forklift load chart answers one question: how much can this truck lift, safely, at this distance and this height. The nameplate number is a single point on that answer — usually the maximum at the rated load center at low lift height. Everything else on the chart is a deration: less capacity as the center of gravity moves out, and less again as lift height rises.
Buyers who read only the nameplate are reading the chart's single best case. Buyers who read the chart are reading the truck.
The four things to find on any chart
- The rating basis. Which load center the chart assumes — 500 or 600 mm — and which standard it follows. Mixing bases between two trucks' charts produces comparisons that look decisive and mean nothing.
- The load-center curve. Capacity falling as the center of gravity moves out. Find your worst realistic load center, not your average one.
- The height curve. Capacity falling with lift height, steepening near full elevation where the mast's own geometry works against stability.
- Attachment notes. Where the manufacturer states the effect of fitted attachments on the chart, usually as a capacity subtraction plus a load-center shift.
| Chart element | What it tells you | Common reading mistake |
|---|---|---|
| Rating basis | Which load center and standard the numbers assume | Comparing charts on different bases |
| Load-center curve | Derated capacity as the center of gravity moves out | Reading capacity at the rating basis when your loads sit further out |
| Height curve | Derated capacity as lift height rises | Assuming the nameplate holds at full mast height |
| Attachment data | Capacity effect of each attachment | Counting only the attachment's own weight |
| Free lift / mast notes | How height behaves in restricted doorways | Confusing free lift with maximum lift |
Reading a chart against a real fleet decision
Consider a buyer deciding between the EP25 and the EP30 for a logistics center with 2,300 kg pallets, occasional 2,700 kg pallets, racking at 4,200 mm and a load center that runs 500-550 mm depending on the goods. The nameplates say both trucks qualify. The chart says more: at 550 mm and full lift height for a 4,200 mm beam level, the EP30 retains comfortable margin while the EP25's derated figure sits close to the occasional heavy pallet. The decision that the nameplates left open, the chart closes — and it closes with margin for the pallet that arrives heavier than its paperwork.
This is the same reasoning our capacity worksheet applies, with the chart as its final step: heaviest realistic pallet, true load center, attachment offset, then the chart at that combination.
Derations stack
The reading error that costs most is treating derations as alternatives. A load at 600 mm center, at height, with a side shifter fitted, is derated three times, and the chart's job is to stack them — typically by reading the load-center figure at height and then applying the attachment effect. If the resulting number is uncomfortably close to the real pallet weight, the truck is the wrong size; margin on a load chart is not padding, it is the difference between a limit and a suggestion.
Stacking also explains a pattern fleet buyers know well: trucks sized by nameplate feel adequate until one specific shift, one specific pallet, one specific top beam — the stacked worst case the chart would have shown on day one.
What we provide with Granvolt trucks
Every Granvolt model page carries the rated capacity and its load-center basis — the EP18 and EP25 at 500 mm, the DF50 at 600 mm, the RT40 at 600 mm — and full load charts are supplied with quotations so the reading happens before the purchase order, not after the first difficult pallet. If your operation has a genuinely mixed load profile, send the profile with the RFQ; reading the chart against your real worst case is a fifteen-minute exercise that our engineering team runs with every fleet quotation, and it is the single highest-value fifteen minutes in the buying process.
Teaching the chart to new operators
A chart that only engineers read protects nobody, because the person making the marginal lift is the operator. Fleets that get real value from load charts translate them into two rules an operator can carry: the derated capacity at the site's common load centers, printed on a card at the dock, and a stop-work threshold — a pallet weight or configuration that requires a supervisor rather than judgment. The full chart stays on file for engineering and audits; the card does the daily work. Sites that run this translation report a further benefit: new operators learn the concept, not just the card, because the card's numbers visibly change with every truck and attachment they rotate onto. The chart is the truth; the card is the truth made portable.
Frequently asked questions
What is a forklift load chart?
A chart showing derated capacity across load centers and lift heights, on a stated rating basis. It shows how much the truck can actually lift in combinations other than the nameplate best case.
Why does capacity fall with lift height?
As the load rises, the combined center of gravity rises and stability margin falls, so the manufacturer derates capacity, steeply near full mast height.
Do load charts differ between 500 mm and 600 mm rating bases?
The basis is stated on the chart and the curves follow from it. Always compare charts that share the same basis, or convert through the manufacturer before comparing.
How do attachments appear on a load chart?
Usually as a stated capacity effect: the attachment's weight subtracted plus a load-center shift for the load it carries. Together these are the residual capacity effect.
Does Granvolt supply load charts with quotations?
Yes. Full load charts accompany every fleet quotation so capacity can be read against your real load profile before purchase.