Manual of basic techniques for a health laboratory - libdoc.who.int

2. Setting up a peripheral health laboratory 17The electrical power of the instrumentThe electrical power is measured in watts (W) and is marked on the plate thatshows the correct voltage for the instrument. Each piece of electrical equipment inthe laboratory uses a certain amount of power. The total power used at any onetime must not exceed the power of your electricity supply. You can work out howmuch power is available from the figures shown on the meter: multiply the voltage(V) by the current (A). For example, if the voltage is 220V and the current is 30A,the electrical power supplied will be 220 ¥ 30 = 6600 watts or 6.6kW.Using a transformerIf an instrument is intended for use with a voltage different from that of the laboratoryelectricity supply, it can be used with a transformer. For example, if the centrifugeprovided only works at 110V and the voltage of your electricity supply is220V, ask for a 110–220V transformer, indicating the wattage of the centrifuge.Plug the centrifuge into the 110V connection of the transformer supplied, thenplug the 220V lead from the transformer into the laboratory electricity supply (wallsocket).Switching off electrical equipmentAfter an instrument has been switched off, it must be unplugged from the wallsocket. If left plugged in, it is a fire risk.2.2.3 What to do in case of failure of electrical equipmentIf an instrument does not work, check the following:— the fuses— the plug at the end of the cable— the cable— the wall socket— the voltage of the instrument and that of the electricity supply.Before doing anything, cut off the electricity supply:— either by pressing the button or the switch marked “OFF” on the meter— or by removing the mains fuse (Fig. 2.5).Tools (Fig. 2.6)●●●●●ScrewdriverWire-cuttersFlat-nose or taper-nose pliersFuse wireVarious spare parts: plugs, switches, etc.Fig. 2.5 Removing the mains fuseFig. 2.6 Tools for electrical work