Flowserve NRS 1-50 For TWO Electrodes - Manual (Page 22)

Measure the electrode voltage in order to check whether the level electrode is immersed or if there is a
malfunction. Please observe Fig. 15.
≈ 0.7 V
85 Hz !
Checking Level Electrodes
Measuring voltage across level electrode
Note
n
The self-checking routine of the level switch NRS -50 reduces U
-
to 0 Volt,
if executed cyclically.
U
- ⊥
Malfunction (immersed/alarm)
U
-
2
<
U
-
2
≥
U
-
U
- ⊥
exposed immersed
b Stand-by input / , 4 V DC, for connecting the logic unit SRL
c Level electrode NRG ...-50, NRG ...-, NRG 6-36
Key
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
NRG 1...-50 NRG 1...-50
1 1 2 2 3 3
NRG 16-36
2 1 4 3
U
-
U
⊥-
U
⊥-
U
-
U
⊥-
U
⊥-
Fig. 15
+ -
b b
+ -
c c
U
- ⊥
≤