This is a question we hear all the time: Can you daisy chain surge protectors? This means, can you plug one surge protector into another and still receive the benefits of protection. Let me ask you this question: Why would you want to do that? If you are attempting to use one surge protector as an extension cord because your other device doesn’t reach your equipment, you should just spend the money on a device that has a lengthier cord. It will save you time and effort and some serious repair or replacement costs.
Daisy chaining surge protectors does not extend any benefits of protection. It does not double your protection either. In fact, hooking your devices up this way may even negate all protection the devices provide. Sometimes surge protectors kick in when power drops below a certain voltage level or exceeds a certain level. What makes this dangerous for two devices running through each other is they don’t determine direction of power flow.
Most plug-in units use MOV technology. MOVs, or metal oxide varistors are semi-conductors that are conducive to heat, meaning they draw heat to them. Any overflow of juice on the power line will be attracted to the MOVs (generally three MOVs to a protector) and drawn to a ground area. The rate at which electricity flows is enough that this can bounce between the two surge protectors, negating any and all protection and even cause some models to shut down.
A major reason not to daisy chain surge protector devices together is the danger of a fire outbreak. Faulty wiring is the main cause of house fires and connecting two devices together may cause overheating of the power line, triggering a fire.
Another lesser reason that makes this dangerous is that electricity can still flow through a surge protector that is turned off. So if you have two devices plugged into one another, you are endangering your electronics and exposing yourself to more problems than if you were to have one long cord surge protector doing the job.
If you wanted to skip the extra purchase and feel it absolutely necessary to use an extension cord, use it on the equipment side of the surge protector. Surge protectors work best when they are closest to the surge source. This would be the outlet where it is plugged. If you decide to do this, make sure the extension cord is plugged into the surge protector and not the other way around. And then you would be best advised to not plug any expensive equipment into the extension cord. Use it for lamps and clocks and suck items that are easily replaced if damaged.