What to pay attention to when selecting dual power switching switches
1. Firstly, determine the type: CB grade or PC grade:
CB level and PC level, in simple terms, CB level has short-circuit protection, while PC level does not.
CB level dual power switching device, with two circuit breakers as actuators, with protection function, and tripping in case of short circuit.
The one below is a PC grade, with a single pole double throw switch as the actuator, without short circuit protection. The protection function depends on the superior circuit breaker.
2. Next, determine the switching method:
The common switching methods include:
Self switching and self recovery
Self switching but not self recovery
Mutual backup
The choice of switching method should be based on the usage situation.
The backup power supply uses a generator and EPS, which is not suitable for long-term power supply. Oil will burn out, and the battery will also run out. To restore the commonly used electricity, it is necessary to self restore it.
Self recovery requires another power outage, such as in the case of a fire fan during surgery, which does not require self recovery. Can be used for non self recovery or mutual backup functions.
3. Precautions for Fire Protection Places
The fire protection function on a dual power supply is called the "fire protection dual separation" function. When receiving the fire signal, both the main and backup power supplies are in the off position.
I once won a bid for a project and had a discussion with the design institute for half a day about whether the fire elevator should use a fire type dual power supply. His drawings are required for use, and I haven't figured them out yet. Who told me.
There is also a word called "fire safety is not important, who knows more?" The editor sincerely seeks guidance.
4. Generator function
The generator cannot be kept on standby for a long time and consumes fuel!
So it is necessary to give the generator a start signal after the common electricity fails, and then close it when the power supply to the generator is normal.
This signal can be obtained from the lead terminals of the dual power supply, and most of the time, it is a passive output.
