Kessel SG 400 V Mono Original Operation Manual page 50

Mono ATEX float switch
Connect the ends of the float switch's leads to the terminal of the Zener barrier [6a].
[6]
50
Zener barrier designation
Alarm = 3, 4 Zener barrier "Mono"
Alarm = 3, 4 Zenerbarriere „Mono"
On= 7, 8 Zenerbarriere „Duo"
Alarm = 7, 8 Zener barrier "Duo"
O = 3, 4 Zenerbarriere „Duo"
Off = 3, 4 Zener barrier "Duo"
A = pump switched off
B = switch pump on
D = alarm
Installation and operating manual
HAZ HAZ
7 8
3 4 3 4
On O
On
Alarm
Off
[6a]
010-532_05