Does the payload rating include my gripper?

No, it's the total at the faceplate, so the gripper counts against it. Whatever the arm is rated to carry has to cover the end-effector, cabling, and any adapter plate first; the workpiece lives in whatever's left.

My load is under the rated mass but the robot still faults or won't run full speed. Why?

Mass is one part of the rating. If the load's center of gravity sits far from the faceplate or its inertia is high, you can be inside the mass limit but outside the torque or inertia envelope, especially at high acceleration or full reach. Set the actual load in the controller so it knows what it's moving.

Can I run above rated payload if I slow the robot down?

Running slower reduces inertial torque, and some arms publish reduced-speed or reduced-envelope load conditions, but that's a manufacturer-defined allowance, not a free pass. Treat the rated payload and its center-of-gravity chart as the boundary and confirm any exception against that specific robot's load conditions.

Performance

Payload

Payload is the mass a robot can carry at its faceplate across the working envelope, and it has to cover everything mounted there, the end-effector plus the workpiece, not just the part being moved.

What it is

Payload is the load rating at the robot's mechanical interface, the faceplate at the end of the wrist. It's the total mass the arm is built to carry and move through its full envelope without exceeding what the motors, gears, and structure can handle.

The number people quote is the maximum, but it's a budget you spend on the whole tooling stack. The gripper, sensor, cabling, and any adapter plate all count against it before you get to the part itself. If a robot is rated for a given mass and your gripper eats a big chunk of that, the workpiece has to fit in what's left.

How it actually works

Rated payload depends on the torque the load puts on each joint, and torque depends on where the mass sits and how it moves. A load's center of gravity offset from the faceplate acts as a lever arm, so the same kilograms mounted farther out demand more wrist torque than mass held tight to the flange. Load inertia matters too: a wide, spread-out load resists acceleration and deceleration harder than a compact one, so a fast-cycling application can be inertia-limited well below the mass limit.

This is why arms come at very different scales for very different jobs. A heavy-lifter like the FANUC M-2000iA/1700L is built for enormous faceplate loads in castings and body-in-white handling, while a small arm like the FANUC LR Mate 200iD carries a light gripper and a small part at high speed. Both live inside their own rated payload with an allowable center-of-gravity envelope; you confirm the actual load with the robot's own load-setting or payload-check function so the servo can tune to what it's really carrying.

How it differs

Rated payload vs total moving mass · Payload is the load at the faceplate, not the robot's own arm mass. The arm's structure and motors are sized separately to move themselves; the payload figure is what you're allowed to add on top, and it already assumes the arm can move itself.
Payload vs reach · Reach is how far the arm extends; payload is how much it can hold there. They trade against each other in a given family, and a load at full extension with a large center-of-gravity offset stresses the joints more than the same mass held close in, so the honest limit is a payload-at-distance figure, not one number in isolation.

Where you meet it in the field

FANUC M-2000iA/1700L · A very high-payload arm, the end of the scale where faceplate loads run into the heavy end of handling and casting work.
FANUC LR Mate 200iD · A small-payload arm for contrast, where the gripper mass is a real fraction of the budget and speed pushes you toward the inertia limit.

Common questions

Does the payload rating include my gripper?: No, it's the total at the faceplate, so the gripper counts against it. Whatever the arm is rated to carry has to cover the end-effector, cabling, and any adapter plate first; the workpiece lives in whatever's left.
My load is under the rated mass but the robot still faults or won't run full speed. Why?: Mass is one part of the rating. If the load's center of gravity sits far from the faceplate or its inertia is high, you can be inside the mass limit but outside the torque or inertia envelope, especially at high acceleration or full reach. Set the actual load in the controller so it knows what it's moving.
Can I run above rated payload if I slow the robot down?: Running slower reduces inertial torque, and some arms publish reduced-speed or reduced-envelope load conditions, but that's a manufacturer-defined allowance, not a free pass. Treat the rated payload and its center-of-gravity chart as the boundary and confirm any exception against that specific robot's load conditions.