Rack Monitor 8800E/8801E
Document: Operation Manual
Date: 16-Jun-2011
Version: A.6
Page 16 of 35 H71343
System operation.
The purpose of the Civacon 8800E Rack Monitor liquid level sensing system is to detect a liquid point level signal
from a sensor mounted in compartments of a tank truck, or storage tanks. The system provides an automatic signal
to the rack automation equipment to shut-off the flow of liquid and warn of an impending overflow condition of a tank
truck or storage tank It can detect up to 8 Two-Wire Sensors or 12 Five-Wire Sensors
As soon as the power is supplied, the monitor will perform a extensive self test of its internal functions (see power
up test). If one of the test fails (except Led Test) a message will be shown on the Liquid Crystal Display. Also a red
Led indicator will blink. (see troubleshooting chapter for details).
Make sure no vehicle is attached at power-up.
Note: The cable and plug connections shall be tested if a active storage hanger is used.
If all tests are passed the rack monitor is ready for use.
The first task of the 8800E Rack Monitor is to ensure proper grounding is established via Pin 9 and pin 10 of the
plug socket connection to the tank-truck chassis. As soon as this has been ensured, two white Led indicators will
flash inversely. Secondly the 8800E will check for shorts between sensors and shorts to ground for every channel
and for open circuits. Then the 8800E Rack Monitor will determine sensor type and the amount of compartments. It
can detect up to eight thermistors or Two-Wire sensors, up to 12 Five-Wire sensors and is fully compatible with the
3204E Onboard Retain Overfill Monitor.
If possible, the amount of sensors will be shown on the Display and Led indicators. ( see sensor detection chapter
for details).
The 8800E Rack monitor provides an “Auto switching” capability between Two-Wire sensors, Two-Wire Thermistor
sensors and Five-Wire sensors.
If sensor type is selected, all sensors are dry and proper ground is verified the 8800E Rack monitor will
communicates a Permissive condition to the automation equipment. When Thermistor sensors are used a waiting
period has to be observed.
Of course the monitor can only be connected to one type of signal source at any one time. You cannot have Two &
Five-Wire sensors connected at the same time. Although the 8800E/8801E Rack Monitor can detect and operate
with a mix of Two-Wire sensors (Thermistor and self oscillating) it is not recommended.
The 8800E Rack Monitor systems uses self-checking principles to provide a continuous check on all system
components. It also checks short circuits between sensors and ground and open circuits when connected to a tank-
truck.
If at any time the 8800E Rack Monitor detects any kind of failure, a signal to the automation equipment will be send
to shut-off the flow
All sensor failures are indicated on the two displays.
