Wilo ER 2, Installation And Operating Instructions Manual

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7
ENGLISH
1 General
Installation and commissioning by qualified personnel only!
1.1 Fields of application
Switch unit for the automatic control of low capacity pump units
consisting of 2 to 4 pumps in conjunction with
– water supply installations,
– fire fighting services.
1.2 Product Specification
1.2.1 Technical data
Power supply requirements: 3~400 V ± 10 %, 50/60 Hz
3~230 V ± 10 %, 50/60 Hz
1~230 V ± 10 %, 50/60 Hz
Control circuit voltage: 24 V DC
Max. switch rating: P2 ≤ 4 kW of each pump at 3~400 V
P2 ≤ 3 kW of each pump at 3~400 V
for 4-pump plant
Max. current rating: 8.5 A
Degree of protection: IP 41
Supply side fuses: 35 A, gL
Ambient temperature: 0 – 40 °C
2 Safety Notes
Safety instructions as laid down in the Installation and
Operating Instructions of the connected pumps must be refer-
red to and strictly complied with.
3 Transport and Storage
The unit must be protected from moisture and
mechanical damage due to impact or shock.
Electronic components must not be subjected to
temperatures outside the limits from 10 °C to 50 °C.
4 Description of Product and Accessories
4.1 Description of the Control Unit
The E conomy R egulating Controller (ER-Control Unit) controls and
manages multi-pump plant up to a maximum of 4 pumps in conjunc-
tion with diverse pressure and level sensors. The pumps are controlled
to switch on or off successively cycle according to water supply
demand. Spreading the total required capacity onto a number of low-
capacity pumps offers the advantage of a rather exact adaption of
plant capacity to actual demand within the respectively most favoura-
ble capacity range of the pumps. This configuration achieves high effi-
ciency as well as the most economical operation of the plant.
The plant is activated for automatic operation and so far at standstill.
If, on opening an outlet fixture the pressure in the distributing pipe
system drops below the switch-on level p
min
the base-load pump will
be activated (Fig. 5, duty curve chart). If the system pressure, due to
increasing supply demand, again drops below the switch-on level, the
first of the peak-load pumps will be activated to run in parallel to the
base-load pump, etc. Inversely, the system pressure will rise with
reduced supply demand. On reaching the first switch-off level p
max1
one of the peak-load pumps will be deactivated. On again reaching
the switch-off level the next peak-load pump will be deactivated, etc.
The base-load pump will only be switched-off at a still higher system
pressure, the 2nd switch-off level p
max2
. At this pressure level the flow
rate is still very low. The switch-on and -off processes of the peak-load
pumps will be time-delayed in order to avoid hunting. The time delay
can be adjusted at the potentiometer (Fig. 2/3, Item P8) between
0 and 2 minutes. The delay action begins with the start of the 1st
pump, but only if the pump(s) had not yet run the set time.
The switch-on and -off levels can be set at the potentiometers p
min
,
p
max1
, p
max2
(Fig. 2/3, Items P5, P6, P7 and Chart I). Switch-off pressure
values 1 and 2 are differential values based on the respectively lower
positioned pressure level. This means that if the pressure settings at
the potentiometers have e.g. been set to p
min
= 4 bar, p
max1
= 2 bar
ATTENTION!
and p
max2
= 1 bar the actual on-/off switch level are: switch-on level 4
bar, 1st switch-off level 6 bar, 2nd switch-off level 7 bar.
4.2 Unit front panel (Fig. 1)
The ER 2/ER 3-4 control unit serves to automatically control a multi-
pump set. The unit front panel contains the following switches or sig-
nals respectively:
–
Main switch
(Item 1) 3-pole (L1, L2, L3)
0
OFF
I
ON
–
2 Selector switches, each one for 2 pumps respectively
(Item 2/3)
0 OFF for both pumps
Manual operation; to start No. 1 or No. 2 pump independent of
current system pressures and without safety functions. WSK- (ther-
mal winding contacts) function remains activated. This switch setting
is intended for test operation only; manual operation runs for approx.
1.5 minutes and will then automatically stop.
Automatic
Automatic operation with all safety functions, electronic
motor overload protection, low-water cut-out.
Automatic 1: No. 1 pump runs under automatic control, No. 2 pump
is switched-off (e.g. due to a fault event).
Automatic 2: No. 2 pump runs under automatic control, No. 1 pump
is switched-off (e.g. due to a fault event).
Automatic 1 + 2: Both pumps operate in peak-duty mode as base-
and peak-load pumps.
No. 2 selector switch: as for No.1 selector switch however, control-
ling Nos. 3. and 4 pumps. With both selector switches set to
Automatic 1 + 2 and 3 + 4 all pumps run in a collective mode as
base-load peak pumps. Stop of one pump in the automatic setting
will not affect the operation of the remaining pumps, which will conti-
nue to run collectively.
– RUN-light (Item 5) for each pump: steady green light indicates
troublefree run of the respective pump, blinking green light on motor
fault.
–
FAULT-light
(Item 4): Red light indicates fault in the water circulating
system.
Options:
– Digital system pressure display
– Hour-run meter for each pump.
– Remote individual fault signalling.
– IP 54 degree of protection.
– Low-water cut out protection.
4.3 Unit functions (Fig. 2/3)
– Integrated electronic overload protection: To safeguard against
motor overloading it is necessary to set the overload cut-out of each
individual motor at its respective potentiometer (Fig. 2/3, Items P1,
P2, P3, P4) to the nameplate FLC-value. WSK-terminals must be
bridged.
–
External overload protection WSK/PTC:
Motors are equipped with
integrated thermal windings contacts (WSK) or with PTC-sensor
require wiring of the WSK or PTC of each motor to the terminals and
setting the potentiometers (Fig. 2/3, Item P1, P2, P3, P4) to its maxi-
mum value (righthand limit).
– Time-delayed switch-off: The time-delay for stopping the base-load
pump to be set at potentiometer (Fig. 2/3, Item P8) between
0 and 2 minutes. It is activated on starting the 1st pump.
–
Low water cut-out:
Pumps used in conjunction with water supply or
fire fighting services must not be allowed to run dry. To protect
from dry-running a pressure limit switch or a float switch are pro-
vided at the unit inlet side which switch-off the pumps in succession
on lack of water. Reset is automatic after restoration of inlet water
availability.
– Overflow alarm: The unit electronics for dry-run protection can also
be utilized for overflow alarm in conjunction with submersible
pumps. This requires switch action reversal by resetting the hook
switch (see Chart 2). On closing of the float contacts the red fault
light will be on, SSM (collective fault signal) will act as an alarm. The
pump however will continue to run. Reset is automatic on ceasing of
overflow.
– Low water cut-out time delay: Times of pump switch off action on
lack of water as well as restart after resetting the fault signal can be