Risatti offers a range of customizable machines for automatic testing and self bonding windings.
The machines created by Risatti perform the following operations and tests:
- Complete test of DUT (stator, windings, etc.): resistance, strenght, rotation sense
- JOULE effect bonding
- Dielectric strength re-testing and SURGE test to highlight any gaps that have occurred
- Stamping
Specifics of bonding windings.
A direct current generator is controlled by a PC of adeguate power in order to deliver the current. Due to JOULE effect, is caused the heating of the windings to the desired temperature in a few seconds. This temperature, about 200°C, induces the softening of the upper layer of the copper wire and the consequent polymerization of itself. In the end the coils are bonded together and to the internal surfaces of the slots.
The parameters are:
- Wire diameter
- Current density (A/mmq)
- Final temperature
The ohmic resistance value is automatically acquired from the previous resistance measurement. The equipment performs the necessary calculations to obtain the resistance value at the final temperature (ΔT) and calculate the power supply voltage suitable for circulating the right current. The generator is direct current, in order to speed up the operation. Dedicated checks detect if faults occur during the bonding windings operation. In this case, they immediately interrupt the process, reporting it to the operator. The windings are bonded in parallel or in series, as required.
The Risatti’s I Series range consists of the following models:
- I12/NCP: operating with 1 or 2 alternate stations with 4 terminals. Suitable for single and three-phase stators up to about 2KW
- I14/NCP-RT: rotary table testing and bonding system for high production – up to 240 pieces / hour
(For the specifics of each machine, please click on link to find out more)