Omron OMNUC U R88M-U Series User Manual page 126

Application
4-3-3 Overload Characteristics (Electron Thermal
Characteristics)
An overload protection function (electron thermal) is built into the Servo Driver to protect
against Servo Driver or Servomotor overload. If an overload (A.70 to A.72) does occur,
first clear the cause of the error and then wait at least one minute for the Servomotor
temperature to drop before turning on the power again. If the power is turned on again
too soon, the Servomotor coil may be damaged.
H Overload Characteristic Graph
The characteristic between the load ratio and the electronic thermal operating time is shown in the fol-
lowing graph.
Note 1. The load ratio is calculated in relation to the Servomotor's rated current.
Note 2. For example, if a current three times the rated motor current is applied continuously, and over-
load will be detected in approximately 3 s.
Artisan Technology Group - Quality Instrumentation ... Guaranteed | (888) 88-SOURCE | www.artisantg.com
Load ratio (%)
Servomotor current
Load ratio (%) =
Servomotor rated current
Chapter 4
× 100
113