Walchem EH Series, Инструкция по эксплуатации

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14
3.3 Calibration
If exact output calibration is required, first prime and
adjust the pump as above. Then connect a calibration
column to the suction side of the pump. Turn the pump
on for one minute and read the amount of liquid pumped
from the column. Adjust the frequency up or down as
necessary and check the output again. When the desired
output is reached, disconnect the calibration column and
reconnect the suction tubing. (See Figure 8.) Calibration
must be performed with application equivalent back
pressure for accurate results.
3.4 External Control
(Not available on EZ pumps)
A. Pumps using the ‘R’ Control Module
For pulse proportional external control of pump frequency, connect the control
signal leads to terminals 4 (positive) and 6 (common) inside the control module.
The input signal should not exceed 360 pulses per minute. The control signal
can be a contact closure type switch or solid state device, however the external
circuit should be capable of switching 10 VDC at 2 mA with a pulse width of 10
ms to 100 ms. (See Figure 9.) Do not use a powered control signal.
In order for the pump to operate properly in External Mode, the frequency knob
must be set fully counter clockwise so it points to the “E”. (See Figure 10.)
2 3
4 5 6
GROUND
POWER
SUPPLY
EXTERNAL
SIGNAL INPUT
TERMINALS
STOP
FUNCTION
TERMINALS
Ho
t
Ne
utr
al
+ (E
XT
)
+
(S
TO
P)
Co
mm
on
Figure 9 Figure 10
100%
STROKE RATE
90
70
50
30
10
E
Figure 8 Calibration