Hi im after some advice, I have recently performed an EICR at a public swimming pool.
Part of the installation uses water level sensors to monitor the level of the pool and automatically top up when the level drops by activating a solenoid valve.
The sensing is performed using "resistive probes" that are fitted directly into the swimming pool via a crouzet HNM control device. The type typically found inside a water tank.
Voltage specs for the sensing device:
'Max. voltage at probe terminals 5 V / 500 Hz ± 10 %
Max. current via probes < 1 mA'
My understanding as per 702.410.3.4.1 is that within the basin of a pool - zone 0 only SELV is permitted. The control device does not state SELV.
Further on in this section is does also state that 'Equipment for use in the of basins which is only intended to be in operation when people are not inside zone 0 shall be supplied by a circuit protected by:
- SELV
- ADS (RCD as per 415.1.1)
- Electrical separation
Now the system is designed only to be energised outside of pool opening hours via a timeclock, however currently none of the above requirements are met.
My assessment is that an RCD needs to be fitted to the circuit, with warning notices to boot letting staff know this should only be used when the pool is closed.
Have I missed anything here or am I correct in my assessment?
In addition the maintenance staff have confirmed this system has been in place for many years and has never been a problem. 