Levelcom 100 - Communication and Calibration Issues

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attached and the LED still doesn’t light and the valve does not operate then there is probably

an electrical problem on the main controller board. If the LED lights but the valve does not

operate the Supply valve has probably failed.

The CALIBRATE menu.

This menu provides utilities for testing and calibrating the LevelCom 100. It is found in the

UTILITIES menu. Below are descriptions of the items in this menu.

The CHAN-0 item gives direct access to the main output from the sensor circuit. When this

item is activated the display shows the output of the analog to digital converter. This output

is also useful to verify that the sensor circuit is functioning. When this item is activated the

valves are all de-energized. The Drain valve is run as a normally open valve so the Drain

port now gives access to the pressure sensor input. It is easy to verify that the sensor circuit

is working by applying a little air pressure to the Drain port and verifying that the numbers on

the display increase with increasing pressure. The ESCAPE key is used to exit this utility.

The CHAN-1 item works exactly like the CHAN-0 item. It gives access to a secondary signal

from the sensor circuit that is used primarily for control of the Supply valve. The ESCAPE

key is used to exit this utility.

The VALVES item gives direct access to the solenoid valves. When activated the front panel

buttons are used to activate the valves.

The following list shows which buttons run which valves.

Button Valve

ENTER Supply

DOWN S.G.

MENU Tank Sense

UP D.P.

ACK Drain

The ESC key is used to exit this utility. This item is useful for testing the valves. This utility

must be used with some caution however. In normal operation the LevelCom 100 is

continually checking the pressure and the Supply valve will be closed if the pressure is too

high. This is done to protect the sensor. When this utility is used the operator must verify

that the sensor does not get exposed to too high a pressure. This is NOT a way to clear a

plugged bubbler pipe for example; the sensor could be permanently damaged this way. It is

also possible, depending on the sense line installation, that liquid from the tank could siphon

back to the LevelCom 100 if the Tank Sense valve is held open for an extended period. This

could result in damaging contamination to the LevelCom 100 and some danger to the

operator depending on the liquid in the tank. It is the responsibility of the operator to use

this utility in a safe manner.

The RELAYS item gives direct access to the relays. When activated the UP button operates

Relay 1, the DOWN button operates Relay 2. The relays de-energize on entering this utility.