If you measure voltages applied to components with that component out of circuit then you are asking to become confused.
A digital voltmeter has an input resistance of perhaps 10 MOhms and will read a voltage which would not exist if the supply was terminated with the normal load. Rub a baloon with a velvet cloth and you can meaasure 1000 volts !
Always measure the voltage across the supply to a fan, pump etc with the component connected. First however measure the resistance of the component to ensure its not short or open circuit. Fans 40-80 Ohms, pumps 150-280 Ohms and gas valves 0.8 -3-2 KOhms.
Tony
A digital voltmeter has an input resistance of perhaps 10 MOhms and will read a voltage which would not exist if the supply was terminated with the normal load. Rub a baloon with a velvet cloth and you can meaasure 1000 volts !
Always measure the voltage across the supply to a fan, pump etc with the component connected. First however measure the resistance of the component to ensure its not short or open circuit. Fans 40-80 Ohms, pumps 150-280 Ohms and gas valves 0.8 -3-2 KOhms.
Tony