Siemens HydroRanger 200, Инструкция по эксплуатации, Страница: 50 / 280

Page 40 HydroRanger 200 – INSTRUCTION MANUAL 7ML19985FC03
mmmm
m
Relay
s
Temperature [6 relay model]
In high alarm, the function goes on when the temperature rises to the ON setpoint and
goes off when the temperature lowers to the OFF setpoint. In low alarm, the function
goes on when the temperature lowers to the ON setpoint and goes off when the
temperature rises to the OFF setpoint.
Loss of Echo
The function goes on when the fail-safe timer expires. The function goes OFF when a
valid echo is received (fail-safe timer is reset).
Pump
Level
In pump down, the function goes on when the level rises to the ON setpoint and goes off
when the level lowers to the OFF setpoint. In pump up, the function goes on when the
level lowers to the ON setpoint and goes off when the level rises to the OFF setpoint.
Miscellaneous
Totalizer and Samplers [6 relay model]
Refer to
Totalizing Pumped Volume
on page 63. Relays are normally de-energized, contact
closure is approximately 200 mSec duration.
Setpoint - ON / OFF
If the ON setpoint is higher than the OFF setpoint, the relay operates as:
• high alarm
• pump down control
If the ON setpoint is lower than the OFF setpoint, the relay operates as:
• low alarm
• pump up control
The ON and OFF setpoints can not be the same on an individual relay but may be common
to other relays. The dead band or hysteresis is the difference between the ON and OFF
setpoints. For in and out of bounds level alarms, the hysteresis is set at
±
2 % of span
from either boundary.