GUARDIAN® M.E SINGLE PHASE PROTECTION PANEL
GUARDIAN® in the standard version comes supplied with the following functions.
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Connection and disconnection directly in line (DOL)
Overload protection Overvoltage and under voltage crowbar
Short-circuit protection
Protection against operating dry (no water protection)
Installation
Ensure that the motor has an earthing cable connected.
Ensure that the system has a gate valve installed just after the base plate. (This is required during the
calibration of the Guardian® panel).
Ensure that the correct cable size is used as per the sizing of the electric motor.
Before the power is supplied to the Guardian® panel, ensure that there is 220 – 230 volt available.
Connect the power supply line as per the instructions in Fig. 1
Connect the output line as per the instructions in Fig. 1
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Grey lead – Main
Brown lead – Auxiliary
Black lead – Common
(4) On Fig. 1 is for all external float and level switches (In the event of none of these switches being
used, the bridge wire must remain in place).
If all the above are correct and in place start the motor (3) on Fig.1
Allow the motor to run for a few minutes to reach its required duty point.
Adjust the potentiometer (1) on Fig. 1 anti-clockwise until the digital panel starts to flash. Thereafter
adjust the potentiometer clockwise until the flashing stops on the digital panel. This has now set the
overload protection.
Close the gate valve on the system (to obtain the minimal amps)
Adjust the potentiometer (2) on Fig.1 clockwise until the digital panel starts to flash “Sb” The electric
motor will now switch off. Thereafter adjust the potentiometer slightly anti-clockwise. Restart the
motor. (If the motor switches off again, re-adjust the potentiometer slightly more in an anti-clockwise
rotation). This has now set the under load protection.
Open the gate valve to obtain the correct duty point of the installation.
The Guardian® ME panel is now calibrated and no further adjustments are required.
In the event of a dry run, (No water) the panel will switch off, and attempt a restart after 10, then 22,
then 45 and finally 90 minutes. If there is still a dry run condition “UL” will flash on the digital display.
Switching the panel off, and then On again will restart the motor once the problem has been resolved.
The display panel will give the following Errors
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Sb – Dry run or low load
UL – Final lack of water (Load disconnected to motor)
OL – Overload (Load disconnected to motor)
(Before the OL is displayed, and the motor is in an overload condition, the overload amps will
flash on the display panel, and will flash until the OL is displayed)
Capacitor Sizing
This protection panel is standard for all single phase size motors, and only the capacitors needs to be
changed to accommodate different size motors. The following table gives the sizing of the capacitors.
Motor Size
0,37KW
0.56KW
0.75KW
1.1KW
1.5KW
2.2KW
Capacitor mf
16
20
25
35
40
60
From 1.1KW to 2.2KW the Guardian® panel only requires a Run Capacitor and no Start Capacitor is
required. (Test carried out has shown that connecting a start Capacitor to the system results in the
running amperage more than doubling, which will cause the motor to fail).
Trouble Shooting
Trouble
The motor does not
start and the
Guardian® displays the
frequency
Guardian® powers the
motor for a fraction of
a second
Display of Sb blinking
Meaning
Self Diagnosis
Possible cause
Supply voltage is to
low
Possible remedy
Check. Must be between
220 and 230V
Self Diagnosis
High voltage drop at
start up of motor
Increase the cross section
of the supply cable
Operating dry or at low
load
Standby time for
restoring level
(10,22,45,90 min)
Final lack of water
(After 4 tests totaling
167 minutes)
No water in the well.
Check
Attention
The load should always
be considered as live
Display of OL
Too high absorption of
current detected
Incorrect adjustment
Display of OL and the
motor is off
Too high absorption of
current detected.
Overload alarm
Display of OF
Missing phase
-The motor does not
start
-Overload
-Pump silted up
-Supply voltage to high
-Unsuitable pump
-Mechanical problems
with the motor
-missing phase
Eliminate the problem
-the motor is not
and reset the Guardian®
connected
Display of UL and the
motor is off
Pump size unsuitable
for the motor.
As Above
Switch off the panel.
Switch on the panel, once
the water level in the
well has recovered.
Check correct absorption
by the motor and
adjustment of the
potentiometer.
(Arbitrarily increasing the
adjustment setting is not
the solution)
Resolve the problem and
rest the Guardian®