Flowserve NRGT26-1 - Manual (Page 18)

8
. Fill boiler or vessel with liquid until the lower measuring point is reached.
2. Wait until boiler or vessel has reached its service pressure.
3. Turn potentiometer
L to the left until the red LED M lights up.
4. Turn potentiometer L to the right until only the green LED N lights up.
You have now established the lower measuring point.
Adjust lower measuring range
Commissioning
Danger
. Check whether the system NRGT 26-, NRGT 26-S has been wired according to wiring diagram
Fig. 13.
2. Check whether mains supply corresponds to the wiring carried out on the equipment.
The terminal strip and the electronic components of the NRGT 26-/NRGT 26-S are live
during operation.
This presents the danger of electric shock.
Use only completely insulated screwdriver according to VDE 0680 for adjusting the
measuring points.
Check wiring
. Turn on power to the equipment. The LED M of the electrode NRGT 26- will light up
(if the electrode is exposed). Fig. 6
Apply mains voltage
. Fill boiler or vessel with liquid until the upper measuring point is reached and wait for
30 secs. (internal attenuation).
2. Turn potentiometer
P to the right until only the red LED O lights up.
3. Turn potentiometer P to the left until the green LED N lights up.
4. Turn potentiometer P to the right until the green LED N goes out.
You have now established the upper measuring point.
5. Fix housing cover
J.
Adjust upper measuring range
■
When adjusting the measuring points of the electrode in a cold liquid, the measuring
points will shift with rising temperature as a result of the longitudinal expansion of the
electrode rod. Be sure to correct the settings accordingly.
■
If a higher accuracy (for 0 % = 4 mA and 00 % = 20 mA) than ± 0.5 mA is required,
measure the level-proportional current at terminals  ü and 2 ä in order to establish
more accurate settings.
Note