CNC Machines

The same ZADMM equipment was found to give different drop reading on different machine. The drop is zero if the Brake coil is new and proper 24V supply to Brake coil. The drop increases when the Brake coil is OLD and/or the Brake coil is weak and the DC supply is NOT properly regulated or fluctuating. In any case the drop is less than 5 ?M with ZADMM installed on your CNC machine.

It can be seen that the delay in servo lock to appear can be calculated by dividing the total drop of spindle in ?M during power failure by a factor of 3. i.e., if the drop of the spindle without ZADMM is 500 ?M, then the delay of servo lock is about 200 mS. This can be reduced to <5 ?M and in many case the drop is 0 ?M by connecting ZADMM.

The drop of the Spindle of the CNC machine is found by placing a dial gauge below the spindle and simulating power failure by switching of the 3-Phase supply. Now connecting the ZADMM to the CNC machine the experiment is repeated. The spindle drop during power failure now with ZADMM will be less than 5 ?M. The theory of how much spindle drops when power fails is explained below.

 

Theory of operation:

 

Variation in types: The equipment can be designed to control up to 3 Brake coils simultaneously. By default one brake coil will be controlled.

Mounting Type:                                  DIN Rail Mounting

Weight:                                              

Dimensions:                                      

3)  Brake connection  - Using 2 LEDs to show correct, No or Wrong connection or AC voltage is supplied for Brake, in which case the SSR will NOT act or control the Brake coil.

                                                              2)   Brake Voltage ON using an LED

Indications:                                         1)   3 Phase supply indicator using 3 LEDs.

Response Time:                                 Less than 0.5 mS equivalent to less than 2 ?M drop on Spindle

Emergency cut0ff output:  Potential Free relay contact

INPUT sensing Voltage: 3 Phase No neutral from 50V to 500V AC @ 50/60 Hz Transformer isolated current drawn < 25 mA per phase.INPUT Working Voltage: Drawn from 3-Phase supplyBrake Coil Voltage:  20V DC to 100 V DC @ 2.5A

Drop on SSR for Braking:  Less Than 0.8V DC @ 2.5A

 

Specifications of ZADMM

There is additional switching point given for simulating emergency condition when the Power failure is noticed and Brake is applied. This connection is explained in the connection diagram.

The Brake coil connection is routed through the SSR located inside our equipment. A control circuit senses this voltage and gives indication of the connection using TWO LEDs. If both LEDs are OFF means the brake voltage is not ON or not connected. If LED1 is alone ON, the Brake coil control is connected properly. If LED2 alone is ON, it means that Brake connection is wrong and needs to be reversed. If both LEDs are ON, the Brake Coil is supplied with AC and hence the SSR will NOT act. In some cases the rectifier for converting AC to DC may be located inside the Brake coil itself. This facility will help the service engineer locate proper wires to be routed through ZADMM.

Being intelligent in assessing the power failure, our equipment knows when glitches and spikes affect the supply and when there is a genuine power failure. So spurious response is largely eliminated. Again the micro-controller is intelligent enough to study the 3-Phase supply to know if it is connected to 3-Phase 400V or 3-Phase 200V supply. There is no jumper change and it is done automatically by the micro-controller. This gives you the freedom to connect ZADMM to any 3-Phase supply.

The CNC machines in India are experiencing severe material or tool damage due to the drop of spindle during power failure. This vexing problem had several organisation and individuals attempting to solve the issue. We are proud to say that we at INTECHSYS, Bangalore had solved the problem with the active help from M/s BFW, Bangalore. As original inventor of the solution, we have been constantly bringing improvement to the equipment and the latest is using very fast acting micro-controller to sense the change in behaviour of the 3-phase supply voltage to cut-off supply to brake coil to arrest the spindle in its position, when the power starts to fail.

INFORMATION/DATA Sheet - ?C based ZADMM (END USER)

Prevent Spindle drop / slide in CNC Machines during power failure. Cost effective solution that replaces diesal generators or UPS.