Product Description:

The JR25M6CH is a permanent-magnet DC servo motor manufactured by Kollmorgen for the ServoDisc Pancake DC Motors series. Its flat armature geometry minimizes axial length, allowing direct mounting in presses, reel stands, and semiconductor handlers where space behind the load is limited. Designed for closed-loop operation with a digital or analog drive, the unit translates commanded current into proportional shaft torque, providing precise speed regulation and position-holding performance in industrial automation. Its 11-inch outside diameter provides a broad air-gap surface that improves torque production without increasing frame height.

A continuous stall torque of 111 lb-in is the maximum torque the motor can maintain at standstill without overheating when the surrounding air is still. Under rated operating conditions, the shaft turns at 3000 rpm when the drive supplies the nominal armature voltage of 150.0 V. At that operating point, the motor delivers mechanical power of 4268 W while drawing a current of 31.6 A. Its zero cogging torque helps prevent cyclic speed ripple, while the torque constant of 65.00 oz-in/A links commanded current to produced torque for precise servo control. A terminal resistance of 0.210 Ω keeps copper losses moderate and supports effective thermal utilization during continuous operation.

For short acceleration bursts, the armature can deliver a peak torque of 1015 lb-in, allowing rapid indexing of heavy payloads before thermal limits are reached. The maximum safe mechanical speed is limited to 5000 rpm, so drive parameters should prevent operation above that ceiling. The motor’s thin rotor has a moment of inertia of 0.700 oz-in-s², enabling fast reversal without requiring excessive drive current. Despite its flat shape, the assembly weighs 70.0 lb, which must be considered when selecting mounts and bearings. An overall length of 7.75 inches keeps the package compact and leaves clearance for couplings or gearheads in crowded equipment bays.