Grundfos ALPHA1 L Series User Manual

English (GB)
14
6.3.2 PWM input signal profile A (heating)
The pump runs on constant-speed curves depending on the PWM
input signal. The speed decreases when the PWM value
increases. If PWM equals 0, the pump runs at maximum speed.
Fig. 17 PWM input signal profile A (heating)
6.3.3 PWM feedback signal
The PWM feedback signal offers pump information like in bus
systems:
• current power consumption (accuracy ± 2 % of PWM signal)
• warning
•alarm.
Alarms
Alarm output signals are available because some PWM output
signals are dedicated to alarm information. If a supply voltage is
measured below the specified supply voltage range, the output
signal is set to 75 %. If the rotor is locked due to deposits in the
hydraulics, the output signal is set to 90 % because this alarm
has a higher priority. See fig. 18.
Fig. 18 PWM feedback signal - power consumption
Data
TM06 9136 1617
PWM input signal [%] Pump status
 10 Maximum speed: max.
> 10 / ≤ 84 Variable speed: min. to max.
> 84 / ≤ 91 Minimum speed: IN
> 91/95 Hysteresis area: on/off
> 95 or ≤ 100 Standby mode: off
TM07 1313 1118
PWM input signal [%]
Max.
Speed
PWM input signal
Max.
Speed
25 50 100 150 200 250
10
20
30
40
50
60
70
80
90
100
Power [W]
Standby (stop)
Alarm stop: fault, blocked pump
Alarm stop: electrical fault
Warning Saturation at 70 Watt
S
l
o
p
e
:
1
W
/
%
P
W
M
Maximum rating Symbol Value
PWM frequency input with high-speed
optocoupler
f 100-4000 Hz
Guaranteed standby power
consumption
< 1 W
Rated input voltage - high level U
iH
4-24 V
Rated input voltage - low level U
iL
< 1 V
High-level input current I
iH
< 10 mA
Input duty cycle PWM 0-100 %
PWM frequency output, open collector f 75 Hz ± 5 %
Accuracy of output signal regarding
power consumption
-
± 2 % (of
PWM signal)
Output duty cycle PWM 0-100 %
Collector emitter breakdown voltage
on output transistor
U
c
< 70 V
Collector current on output transistor I
c
< 50 mA
Maximum power dissipation on output
resistor
P
R
125 mW
Zener diode working voltage U
z
36 V
Maximum power dissipation in Zener
diode
P
z
300 mW

Grundfos ALPHA1 L Series Specifications

General

Pump Type	Circulator
Series	ALPHA1 L
Max Head	6 m
Voltage	230 V
Frequency	50/60 Hz
Liquid Temperature Range	2°C to 110°C
Max Operating Pressure	10 bar
Insulation Class	F
Enclosure Class	IP42
Application	Heating systems
Control Modes	Proportional pressure, constant pressure
EEI	0.20
Material	Cast iron
Power Input	Varies by model (e.g., ALPHA1 L 25-40 180: 3-22 W)
Pipe Connection	G 1 1/2