The failure of each tool position of the electric tool holder of CNC machine tools to rotate continuously is mainly caused by the following aspects:

① The CNC machine tool system does not have +24v;com output; use a multimeter to measure the system outlet to see if the output voltage at these two points is normal or exists. If the voltage does not exist, it is a system failure and the motherboard needs to be replaced or sent to the factory for repair.

② The CNC machine tool system has +24v; com output, but the connection with the tool holder sending board is open circuit; or +24v is short-circuited to com ground; use a multimeter to check whether there is an open circuit between +24v on the tool holder, com ground, and the system; check whether +24v is short-circuited to com ground, and pull down the +24v voltage.

③The CNC machine tool system has +24v; com output, and the connection is normal. There is an open circuit in the +24v and com ground loops on the sending circuit board of the sending board. The sending board has been in a humid environment for a long time, causing the circuit to be oxidized and broken. Use solder or wires to reconnect.

④The +24v voltage at the tool position of the CNC machine tool system is low, and the pull-up resistor on the line is open circuit; use a multimeter to measure whether the voltage at each tool position is normal. If it is low, check the pull-up resistor. If it is open circuit, replace the 1/4w2k pull-up resistor.

⑤ The system's reversal control signal tl- has no output; use a multimeter to measure the system outlet to see if the output voltage at this point is normal or exists. If the voltage does not exist, it is a system failure and the motherboard needs to be replaced or sent to the factory for repair.

⑥ The system has a reverse control signal tl- output, but there is a problem with the circuit between the tool holder motor and the tool holder motor; check whether there is a break in each intermediate connection, check whether each contact is in poor contact, and check whether the DC relay and AC contactor in the high-voltage cabinet are damaged.

⑦ The tool position level signal parameters are not set properly; check whether the system parameter tool position high and low level detection parameters are normal and modify the parameters.

(Source: Electrician Electrical Technology Exchange)