74
control on constant Flow
problem: control Fluctuations
cause:
check:
• Increase WINDOW [0310] and set
Control characteristics are set too low
HYSTERESIS [0315] to 99% to control with
RAMP 3 and 4.
circulating pump
problem: oscillation of the motor speed
cause:
check:
• Increase RAMP 3 [0225] and 4 [0230]:
Control settings too fast
100...200sec.
• WINDOW [0310] (20%) and HYSTERESIS [0315]
(99%).
problem: actual Value can't be maintained
cause:
check:
HYSTERESIS is set too big
HYSTERESIS [0315]: 90-99%
General
Problem: Pressure fluctuations, analogue signal not constant
Solution:
• Check cables and connection of the screen
• Check earth connection of the transmitter cable
• Use screened cables
Failure MessaGes
