When helping a customer specify and design a slip ring, one of the most important pieces of information is the circuit ratings. A common question customers ask UEA is how many amps can we put through a slip ring or at what voltage? This is a bit of an open ended question as UEA is a custom slip ring manufacture who continues to broaden our product range.
The normal maximum ratings would be 600 amps and 600 volts. This is what UEA’s “standard” slip rings are designed for. This, however, depends on the size of the slip ring, which can be driven by the application and the customer’s needs. The limiting factor for current ratings in smaller rings is the size of wire/buss bar you are able to get inside the core of the slip ring.
UEA is a custom ring manufacturer, so we have certainly worked with higher amperages and voltages. We build rings weekly that are rated 690 volts up to 1000 volts, and we could certainly go higher given adequate room. We have also designed specific assemblies to handle up to 900 amps in specific applications. Things do get more difficult with these ratings and spacings; sizes of conductors must grow so the entire assembly will begin to get very large.
One question often asked is if the slip rings are de-rated when not rotating. In UEA’s case, no. Our rings are designed for continuous power. Meaning, if we rate a circuit to handle 50 amps, it will handle 50 amps 100% of the time whether it’s rotating or not. Another question that often gets asked is in regards to very low or no current or voltage applications. Our slip rings and brushes are designed to also run “dry” with no current or voltage. So, in applications where we just have a ground or shield or very low currents, there are no issues.
Again, UEA’s standard slip ring line is designed to handle up to 600 amp and 600 volts, but we focus on providing solutions for our customers and often that requires UEA to make a custom design or application-specific slip rings.
Sr. Application & Design Engineer
Pictured below: Slip rings containing several different current and voltage configurations.