Table of Contents
Advertisement
9 7 Dry running protection
The well probe, cf. "Figure 29: Well probe", contains a
mechanical float with a magnet inside. When the probe
is submerged, the float rises, and the magnet actuates a
switch. The switch closes (makes contact) to indicate the
presence of water. If the water level drops below the probe,
the float drops, and the switch opens (breaks contact): The
controller will stop the pump. When the water level recov-
ers and switch closes again, the controller will delay the
restart for 15 minutes. This gives time for the water level to
recover. To force a quick restart, turn the controller off, then
on again. The switch is sealed, so the contacts never touch
the water.
Fixing – The probe is packed with two cable ties. For a
pump that is to be installed in a vertical position, clamp it
to the pipe just above the pump outlet, as shown below
"Figure 30: Well probe fixing". Splice the two probe wires
using the splice kit components that are packed with the
probe. The assembly procedure is the same as the main
pump splice.
Wiring to the controller – The dry run protection must
be connected to the controller via plug at slot B8, cf. "8.4.4
Cable entries and external sockets" on page 14.
Potential problems with the low-water probe in
surface water – The probe has a moving float. It is highly
resistant to deposits and debris. However, it may stick
under some extreme conditions, especially from algae or
water creatures (snails, etc.) that may be present in surface
water.
Possible solutions are:
ƒ Hang the probe independently of the pump and pipe
(clamped to a weight, but not to the drop pipe). This
way, it can be pulled up for inspection or cleaning
without the need to pull up the pump. (This may not
be feasible if the well casing is smaller than 6 in)
ƒ Pull the probe out periodically (with the pump, if
necessary) for testing and inspection. The pump should
stop at the moment the probe leaves the water.
ƒ Wrap the probe in a protective screen (fiberglass win-
BERNT LORENTZ GmbH & Co. KG Kroegerskoppel 7, 24558 Henstedt-Ulzburg, Germany, Tel. +49 (0) 4193 7548 - 0, Fax - 29, www.lorentz.de
All specifi cations and information are given with good intent, errors are possible and products may be subject to change without notice. Pictures may
differ from actual products depending on local market requirements and regulations.
dow screen, for example). Substitute a different type
of float switch. You can use any switch that makes
contact on rise (normally open).
ƒ Use an encapsulated switch instead of the well probe
if there is enough space for it to operate propery, for
example the LORENTZ float switch.
CAUTION – Running completely dry
will damage the pump and void the
warranty The purpose of the probe
system is to sense the loss of water
and turn the pump off before it can
run dry
CAUTION – The low-water probe
must be positioned vertically, within
10° If the pump is NOT to be
installed vertically, find an
alternative way to mount or
suspend the probe, so that it is
higher than the pump, and in a
vertical position
Figure 29: Well probe
26
9 7 1 Water detection sensor
CAUTION – For submersible pumps a
jumper cable between the terminals
1 and 2 has to be installed
The terminals 1 and 2 inside the PSk2 controller are for
connecting the LORENTZ water detection sensor, cf. chapter
"8.4.3 Terminal description" on page 13.
This sensor is ONLY installed with surface pumps . For
operation with submersible pumps the terminals 1 and 2
need to be bypassed with a jumper cable. If the jumper is
not in place the controller will show "Source Low" and the
pump will not run.
Figure 30: Well probe fixing
Sun. Water.
Life.
Advertisement
Table of Contents
