Mitsubishi Electric CR750-Q Instruction Manual page 528

5Functions set with parameters
Note that the actual override in the warm-up operation status is as follows:
• During joint interpolation operation = (operation panel (T/B) override setting value) x (program override
(Ovrd instruction)) x (joint override (JOvrd instruction)) x warm-up operation override
• During linear interpolation operation = (operation panel (T/B) override setting value) x (program override
(Ovrd instruction)) x (linear specification speed (Spd instruction)) x warm-up operation override
Note 1:If the MODE switch on the controller's front panel is set to "TEACH," or for a jog operation or an
operation by real-time external control (MXT instruction), the warm-up operation override is not
reflected and the robot operates at the originally specified speed.
Note 2:In the warm-up operation status, because the robot operates at a speed lower than the originally
specified speed, be sure to apply an interlock with peripheral units.
Note 3:If a multiple number of target axes exist, the warm-up operation override is calculated using the
minimum operation time among the target axes. If a certain target axis does not operate and the
value of the M_Wuprt status variable does not change, the value of the warm-up operation over-
ride does not change regardless how much other target axes operate.
Also, the value may return to the initial value before reaching 100% depending on whether each
target axis is operating or stopping.
For example, when the value of a warm-up operation override is larger than the initial value, if a
certain target axis switches from the normal status to the warm-up operation status, the operation
time of that axis becomes the smallest (the operation time is 0 sec) and the warm-up operation
override returns to the initial value.
(3) If alarms are generated
1) An excessive difference error occurs even if operating in the warm-up operation status.
• If an error occurs when the warm-up operation override is set to the initial value, decrease the value of the
initial value (the first element of the WUPOvrd parameter).
• If an error occurs while the warm-up operation override is increasing to 100%, the valid time of the warm-
up operation status or the value constant time may be too short. Increase the value of the first element of
the WUPTIME parameter (valid time) or the second element of the WUPOvrd parameter (value constant
time ratio).
• If an error cannot be resolved after taking the above actions, change the operation program, and lower the
speed and/or the acceleration/deceleration speed.
2) An excessive difference error occurs if the warm-up operation status is canceled.
• Increase the value of the first element of the WUPTIME parameter, and extend the valid time of the
warm-up operation status.
• Check to see if the robot's load and the surrounding temperature are within the specification range.
• Check whether the target axis continues to stop for an extended period of time after the warm-up opera-
tion status has been canceled. In such a case, decrease the value of the second element of the WUP-
TIME parameter, and shorten the time until the warm-up operation status is set again.
• If an error cannot be resolved after taking the above actions, change the operation program, and reduce
the speed and/or the acceleration/deceleration speed.
3) The warm-up operation status is not canceled at all.
• Check the setting value of the WUPAXIS parameter to see if a joint section that does not operate at all is
set as a target axis in the warm-up operation mode.
• Check to see if a target axis has been stopping longer than the resume time (the second element of the
WUPTIME parameter) of the warm-up operation status.
• Check to see if an operation is continuing at an extremely low specified speed (about 3 to 5% in override
during joint interpolation). If the specified speed is low, there is no need to use the warm-up operation
mode. Thus, disable the warm-up operation mode.
5-508 Warm-Up Operation Mode