Pump Controls; Commissioning The Pump; Calibration; Pb-Rx Specific Electrical Fault - Etatron PB Serie Manual Del Usuario

11.4 - PB-RX PUMP CONTROLS (Fig. 29)
1 - ON/OFF light switch "green"
2 - Level alarm L.E.D. "yellow"
3 - Pulse frequency L.E.D. "red"
4 - Injection frequency adjustment knob
5 - RED/OXI selector
6 - Redox signal L.E.D.
7 - Oxid signal L.E.D.
8 - Gain calibration

9 - "0" calibration

10 - 4 digits display
12 - Set calibration trimmer
13 - Meter/set point selector

11.5 - COMMISSIONING THE PUMP

A. Install the metering pump as described in Chapter 3.0 "PUMP INSTALLATION".
B. Place the electrode in the electrode holder.
C. Connect the electrode to the metering pump by means of the male BNC connector (T) rotating it through
90°C.
D. Position the "FUNCTION SELECTOR" (13) at set and then use the tool supplied with accessories to adjust
the "set" (12) trimmer to the required value.
E. Position the function selector (13) at "met". Use the "RED/OXID" switch (5) to select the required type of
intervention (reduction or oxidation). Example: if the intervention point is set at 700 mV and an oxidation is
required, set the switch to OXID. The pump will then start dosing the additive every time the solution poten-
tial drops below 700 mV. If it is desired to perform a reducing action, set the switch to RED, in which case
the pump will come into operation every time the solution potential rises above 700 mV. Bear in mind that
Redox measurements are affected by pH variations; if this factor is subject to considerable oscillations, we
would advise that PB-RX pump can be supplemented with either an PH pump or pH instrument combined
with a dosing pump.
F. Use the FLOW knob (4) to set the number of pulse per minute, reducing or increasing the pump discharge
according to requirements. In this connection it must not be forgotten that adequate time must be allowed
for the additive to become uniformly distributed, otherwise the value read on the display will differ from the
real system state.
All our pumps are tested at their maximum working pressure; consequently, if the plant is operating at a
lower pressure, the maximum discharge of the pump may be greater than the specified value.
11.6 - CALIBRATION
Disconnect the electrode from the pump and short-circuit the female BNC connector of the pump by the use of
copper wire, then use the plastic tool supplied with accessories to turn the potentiometer marked "0" (9) until
the display reading become 00. Then connect the electrode and immerse it in a buffer solution of well defined
mV value, agitate the solution and after few seconds rotate the potentiometer "mV" (8) until the correct mV
value of the buffer solution is read on the display.
11.7 - PB-RX SPECIFIC ELECTRICAL FAULTS
THE PUMP DOES NOT MEASURE CORRECTLY
a) Check the calibration of instrument
b) Check the efficacy of the electrode
THE PUMP FAIL TO DOSE
a) Make sure the "set point" has been correctly set
b) Make sure the "RED/OXY" switch is on the right position, i.e. that it concords with the required dosing.
N.B. When removing the pump from the plant use great care in detaching the delivery hose from the connector
nipple because it could contain some residual additive.
• 51 •
PB-RX
Fig. 29