Standby power of electric shower

[treez]

Hello,
What is the standby power of this electric shower?
https://www.mirashowers.co.uk/onlinecatalog/detail.htm?productNumber=Advance ATL Flex 9.8kW&section=Electric showers&resultPageKey=316145834-0&category=


is it true that showers are classed as industrial equipment, and as such are exempt from standby power regulations?

 

[betwixt]

You will have to write to Mira. Their web site is missing the PDF file from their products page.

There is nothing to put in 'standby' on a shower unles it's something cosmetic like a digital clock or a power indicator so I would guess it's almost zero like any other shower. Most have pressure switches after the flow control to completely cut the power if the water pressure is too low so when they are off, the electrical supply is disconnected.

Not sure about being industrial - sounds strange if they are.

Brian.

 

[treez]

With the electric showers, something has to power the toggle flip flop which turns on/off the solenoid valve.
The toggle flipflop answers to the momentary pushbutton switch.....the T flipflop switches on a fet which pulls current through the coil of the solenoid, thus turning on the shower.
Also, there are usually some leds which take power.

The origin of this power is the 230vac mains.
Unless the power is gotten by efficient smps then the standby power can be 1w , say

 

[betwixt]

I've converted to a solar heated shower (probably why the weather has turned so bad!) so I can't confirm from what I have here. I have a holiday chalet with a new electric shower though and I don't recall seeing any PSU or even a circuit board inside it but it does have indicator lights and an 'overrun' timer to flush remaining hot water out of it. The circuit must be very small so I would guess it's nothing more than an SCR or triac in series with the solenoid and a simple DC trigger to it using a diode and resistor with a capacitor to give the time delay. I'm pretty sure the lights are neons. If I am correct, the 'standby' current would be microamps.

Brian.

 

[treez]

The one I have seen, it has a cct board......the mains is rectified.....then a zener/bjt linear regulator provides a ~few mA rail at 5v which feeds the toggle flip flop...the t flipper turns on the fet which ends up making current go through the coil of the solenoid........I have forgotten now whether the fet switching on turned on the AC solenoid, as I think it was an ac solenoid.....I don't remember any other semiconductor switch other than the fet.....I don't remember any scr or anything else.....................the solenoid had a fair old bit of coil resistance....I do remember that..it was something like 1K, so the solenoid ran well hot.

I distinctly remember that the R/ZENER/BJT regulator pulled about at least 500mW of standby power......(when the shower is on but water is off)