Q7: What is regenerative resistor? How to connect a regenerative resistor? What kind of situation that needs to use the regenerative resistor?
A7: When the output torque of servo motor in reverse direction of motor rotation speed, it indicates that there is a regenerative power returned from the load to the servo drive. This power will be transmitted into the capacitance of DC Bus and result in rising voltage. When the voltage has risen to some high voltage, the servo system needs to dissipate the extra energy by using a regenerative resistor. ASDA-A series servo drive provides a built-in regenerative resistor and the users also can connect to external regenerative resistor if more regenerative capacity is needed.

When using an external regenerative resistor, connect it to P and C, and make sure the circuit between P and D is open. When using a built-in regenerative resistor, connect it to P and D, and ensure an open circuit between P and C.

When the regenerative power exceeds the processing capacity of the servo drive, the fault, ALE05 may occur. At this time, please install an external regenerative resistor.

Q8: How to choose adequate external regenerative resistor? If there is a simple method for the users to select the regenerative resistor conveniently?
A8: The users can select the adequate regenerative resistors according to the allowable frequency required by actual operation and the allowable frequency when the servo motor runs without load. The allowable frequency when the servo motor run without load is the maximum frequency that can be operated during continuous operation when servo motor accelerate from 0rpm to rated speed and decelerate from rated speed down to 0rpm. The allowable frequencies when the servo motor run without load are summarized in the following table.

Servo Motor Models	Allowable frequency when the servo motor run without load (times/min)
	100W	200W	400W	750W	1.0kW	1.5kW	2.0kW	3.0kW
	01	02	04	07	10	15	20	30
ASMT L Series	12133	2022	1071	337	140	100	155	63
ASMT M Series	-	-	-	-	136	93	104	38

When the servo motor runs with load, the allowable frequency will change according to the changes of the load inertia and rotation speed. Use the following equation to calculate the allowable frequency.

m = load/motor inertia ratio
The users can select the adequate regenerative resistors according to the allowable frequency by referring to the table below:

Q9: How many groups of Delta servo drive parameters? What are Delta servo drive parameter groups?
A9:
There are five groups for drive parameters, which are:
Group 0: Monitor parameter (example: P0-xx)
Group 1: Basic parameter (example: P1-xx)
Group 2: Extension parameter (example: P2-xx)
Group 3: Communication parameter (example: P3-xx)
Group 4: Diagnosis parameter (example: P4-xx)

Q10: What is the meaning of the symbol marked after parameter code? What should the users pay attention to it?
A10:
The explanation of symbols marked after parameter codes are shown as the following. Please pay close attention to it before setting these parameters.
(★) Read-only register, such as P0-00, P0-01, P4-00.
(▲) Parameter cannot be set when Servo On (when the servo drive is enabled).
(●) Parameter is effective only after the servo drive is restarted (after switching power off and on), such as P1-01.
(■) Parameter setting values are not retained when power is off.

Q11: How to monitor the status of the servo drive via the digital keypad?
A11:
The users can use parameter P0-02 directly to specify the monitor status and change it via UP and DOWN key on the keypad. When the power is applied, the monitor status depends on the setting value of P0-02. For example, if the setting value of P0-02 is 2 when the power is applied, the monitor function will be Pulse counts of pulse command, the C.P monitor codes will first display and then the pulse number will display after.