Gas heaters produce more heat when compared to electric heaters in the same amount of time. Since gas is generally cheaper than electricity, a gas heater has lower operating cost.Electric space heaters are cheaper only when a small space is to be heated at lower temperature settings.as heaters produce more heat when compared to electric heaters in the same amount of time. Since gas is generally cheaper than electricity, a gas heater has lower operating cost.
EPNS stands for Electro Plated Nickel Silver. Nickel Silver (sometimes stainless steel) is the base metal onto which silver is plated. Despite its name, nickel silver contains no silver at all, but is an alloy of nickel, zinc & copper.he most common is EPNS (Electro Plated Nickel Silver) but many other symbols are used: 1  EPBM (Electro Plated Britannia Metal). 2  EPCA (Electro Plated Copper Alloy). 3  ESM (Electro Plated Silver Mounts).
Now, one of the old guys! In PLC work NPN means the sensor or switch connects to the negative of the power supply. When the sensor is made up it connects the plc input to the negative and makes up the PLC input point. The PNP is the same except it connects the PLC input to the positive side of the supply. In most of my plc work we use NPN type sensors.