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What is the correct load capacity of the HS200 switch?

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What is the correct load capacity of the HS200 switch?

This thread has been locked for further replies. You can start a new thread to share your ideas or ask questions.
What is the correct load capacity of the HS200 switch?
What is the correct load capacity of the HS200 switch?
2017-11-07 00:29:59
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I see that the HS200 switch is specified in various places (including TP-Link's web site) as having a capacity of "100-120v, 15 amps" and also "600 watts incandescent". Obviously these two specs are inconsistent, so which is correct?

The wall plugs are consistently specified as 15 amps or 1600 watts, so one might assume that there's a misprint in the HS200 spec, and they meant 1600 watts rather than 600 watts.

But it's also common for devices that use thyristor-type electronic switches to have lower load limits than a relay switch, and they may also be sensitive to the inductance/capacitance of the load. The term "incandescent" is often used as a shorthand to mean "resistive load" since an incandescent bulb is a pure resistive load, whereas florescent and LED bulbs may present capacitive/inductive loads. This term's presence suggests that the HS200 might be such a switch, in which case it could be the 15 amps that's wrong.
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Re:What is the correct load capacity of the HS200 switch?
2017-11-07 10:21:30
The HS200 can only accept at most 600W of incandescent bulbs, since the incandescent lamp has a very high instantaneous current (more than 15A) at the moment when the incandescent lamp is switched on.For other power devices, HS200 can accept 1800W (120V*15A) at most (for the US version).
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Re:What is the correct load capacity of the HS200 switch?
2017-11-07 11:59:40

Kevin SG wrote

The HS200 can only accept at most 600W of incandescent bulbs, since the incandescent lamp has a very high instantaneous current (more than 15A) at the moment when the incandescent lamp is switched on.For other power devices, HS200 can accept 1800W (120V*15A) at most (for the US version).


Sorry, but that's not correct. Incandescent light bulbs are a pure resistive load. There is no surge current when they are turned on.

The box says Input: 100-120v 15 amps (0.3 amps product only), Output: 600 watts (incandescent)

That's also a bit nonsensical, since there's no way the switch is going to draw 15 amps when driving a resistive load of maximum 600 watts. They seem to be trying to say something about non-resistive loads, but they've failed to make it clear.
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Re:What is the correct load capacity of the HS200 switch?
2017-11-07 16:36:08
I believe that 15A and 600W Incandescent are two different things TP-Link want to express, but it doesn't make it clear that they are different.
15A is the common load and 600W Incandescent is a special case.
The 600W Incandescent should be the test result, otherwise it will not be specially written on the website.
You can send a feedback to TP-Link about this issue.
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Inrush Current
2017-12-16 04:43:18
Sorry, but that's not correct. Incandescent light bulbs are a pure resistive load. There is no surge current when they are turned on.

The box says Input: 100-120v 15 amps (0.3 amps product only), Output: 600 watts (incandescent)

That's also a bit nonsensical, since there's no way the switch is going to draw 15 amps when driving a resistive load of maximum 600 watts. They seem to be trying to say something about non-resistive loads, but they've failed to make it clear.


Your math is correct; unfortunately, your understanding of "incandescent" lamps is not.

Yes, an incandescent is a "purely resistive" load; the problem is, the resistance changes as the filament heats up. Take an ohm meter to a cold incandescent bulb. You will find the resistance value you obtain (~0.0X ohms) is not consistent with the rated wattage of the bulb. Using the "IR-squared" formula, a 100 watt bulb should have about 144 ohms of resistance -- and it does... once it gets hot! (I*R*R=100W; 144Ohms * 0.83Amps * 0.83Amps = 100 Watts). Depending upon the bulb(s) deployed and how fast it (they) heat, the transition from ~0.0X ohms to 144ohms can take anywhere from a few milliseconds to nearly one (1) second.

Apparently, whatever circuitry they use in the HS200 Switch cannot handle the accompanying inrush current. My guess would be, they have spec'd it to handle one (1) 600watt bulb; six (6) 100watt bulbs would tend to heat more quickly -- you might be able to push the spec a bit...

I would also guess that the "Maximum Power = 3.68KW" line is a reference to that ability of the device to handle up to a 30 Amp inrush current -- for a brief (less than one second?) period of time -- but that is just a guess...


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