Omron SMARTSTEP Junior R7D-ZP, Руководство пользователя

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3-2 Servomotor Specifications
3-2-3 Encoder Specifications
Temperature Characteristics of the Servomotor and Mechanical
System
• SMARTSTEP Junior Servomotors use rare earth magnets (neodymium-iron
magnets). The temperature coefficient for these magnets is approximately –0.13%/°C.
As the temperature drops, the Servomotor's maximum momentary torque increases,
and as the temperature rises, the Servomotor's maximum momentary torque
decreases. The maximum momentary torque is about 4% higher at –10°C compared to
the normal temperature of 20°C. Conversely, the maximum momentary torque
decreases about 8% when the Servomotor warms up to 80°C from the normal
temperature of 20°C.
• Generally, when the temperature drops in a mechanical system, the friction
torque and the load torque increase. For that reason, overloading may occur at low
temperatures. In particular, in systems that use a Decelerator, the load torque at low
temperatures may be nearly twice the load torque at normal temperatures. Check with
a current monitor to see whether there is overloading at low temperatures. Also check
operation at high temperatures to see whether there is abnormal Servomotor
overheating or alarms.
• An increase in load friction torque visibly increases load inertia. Therefore, even
if the Servo Driver parameters are properly adjusted at a normal temperature, the
Servomotor may not operate optimally at low temperatures. Check operation at low
temperatures to see whether operation is optimal in those conditions, too.
3-2-3 Encoder Specifications
Item Specification
Encoder method Optical encoder (incremental encoder)
Number of output pulses
Phase A, B: 256 waves/revolution
Phase Z: 1 pulse/revolution
Power supply voltage 5 VDC ±5%
Power supply current 70 mA max.
Output signals +A, –A, +B, –B, Z, U, V, and W
+A, –A, +B, and –B Sine wave voltage output
Output interface
Z, U, V, and W Transistor output
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