HH15-QA is defined as

The disconnect switch utilized on a recent building site, where a current of 250A must be removed and the box size is limited. We eventually recommended a fuse-type isolation switch-HR6 fuse-type isolation switch to him after weighing the price, size, and other criteria. However, the client did not grasp the fuse type isolating switch very well, and we also explained patiently, but after some thought, some people inquired what the difference was between the HH15-QA switch type isolating switch and the common isolating switch. So, based on my personal experience and information gleaned from the Internet, here is a quick explanation of what the HH15-QA chint switch disconnector is.

We know that the general isolation switch’s primary function is to disconnect a little current and modify the operating mode. I’m not sure if you discovered it or not. One of them is to cut off the little current, which is the source of the problem. When the current exceeds a specific level, it may cause damage to the isolation components in the isolating switch, rendering the switch inoperable. With this in mind, it is required to supply a fuse (equivalent to a fuse) for protection in order to be able to disconnect significant currents and, more critically, to safeguard the isolation switch in the face of such isolation. The switch is now known as the HH15-QA switch disconnect switch, which is more formal. It is defined as follows: A fuse disconnect switch must fulfil the following three requirements:

  1. Use a fuse to protect the switch.
  2. In this case, It can make, carry, and break current under normal circuit circumstances (including defined overload), and it can carry current isolating switch under specified abnormal circuit situations (such as short circuit) and within set period.
  3. When in the open position, the circuit can offer safety isolation to ensure circuit breaking and safe operations.

Then include some information about the fuse disconnector. In general, this style of isolating switch is mostly utilised for traditional line protection. It is not commonly used as a motor switch because the breakdown current of the motor during starting and stopping is very high, making it very easy to destroy the HH15-QA fused isolating switch. Again, even when the rated heating current of the switch is the same, the fuses used are not the same, as in the case of the HH15-QA switch disconnector discussed at the beginning of the article. When the rated current is 100A, the fuse link should be NT00, and when the current is 250A, the fuse link should be NT1. To prevent unneeded difficulties, we must pay more attention when purchasing fuse-type isolating switches and select the suitable model based on our specific scenario.

Application range

HH15-QA series fuse set, HH15 (QA), HH15P (QP) series isolating switch, zzHH15S (QSS), HH15AS (QAS), HH15PS (QPS) series double throw transfer switch (hereinafter referred to as switch), It is appropriate for power distribution and motor circuits that require a high short-circuit current with AC 50Hz, a rated voltage of up to 660V, and a conventional heating current of up to 3150A. It is utilized as the main switch or main switch for manual rarely operation, with the QA and QSS series switches being suitable for circuit short circuit safety.

Structural characteristics

  1. The switch operates in a frontal rotation mode and is made up of an operating mechanism, a contact system, and a handle.
  2. The switch has a fully enclosed structure, with the static contacts and arc extinguishing system housed in a shell made of new arc-resistant engineering plastics; it also has spring energy storage, instantaneous release acceleration closing mechanism, which greatly improves the switch’s efficiency. The switch’s electrical and mechanical qualities are enhanced.
  3. The switch includes a contact system that performs exceptionally well. The moving contact system is made up of four copper rollers that are held together by compression springs. Each roller may move independently, preventing contact welding more efficiently; when a fault arises, the contact pressure increases with the increase in current, allowing the switch to resist a significant short-circuit current.
  4. The HH15A (QA) isolation switch’s contact system is made up of double contacts in series, the HH15P (QP) isolation switch’s contact system is made up of double contacts in parallel, and the double throw transfer switch is made up of two corresponding single contacts. Side by side, the cast switch is created.

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