Endress+Hauser nivotester FTC 420 - F; Fail-Safe Mode

Selection of fail-safe mode The fail-safe mode is controlled by a bridge between terminals 12
and 13 of the Nivotester. The function can be taken from Table 2,
Fig. 7 and Fig. 8
Minimum Fail-safe mode
Maximum Fail-safe mode
1) Relay status on power failure. The green and red LED go out.
Nivotester Maximum
bridge 12-13
Minimum
no bridge 12-13
FTC 420 Relay de-energises at
maximum and on
power failure. The red
LED lights
Relay de-energises at
minimum and on power
failure. The red LED
lights.
FTC 421 Relay de-energises at
maximum after selected
delay and on power
failure. The red LED
lights
Relay de-energises at
minimum after selected
delay and on power
failure. The red LED
lights
Table 1
Truth table for fail-safe mode
Klemmen
12 - 13
Level Relay LED
Fig. 7
Minimum fail-safe mode
1)
1)
Klemmen
12 - 13
Level Relay LED
Fig. 8
Maximum fail-safe mode
Nivotester FTC 420/421 Installation
28