HT-100R Series
HITROL CO., LTD.
12
Maintenance
The major parts of the HT-100R(-Ex) Series level transmitters to be inspected are divided into the
sensor element and the transmission element. The sensor element consists of Reed Switch,
Resistors, and the Float, and the transmission element is the M-100R(R/I CONVERTER). The life
spans of major parts vary with user environments and can be used in optimum conditions
through periodic inspections. Therefore, the user should maintain and repair the product through
periodic inspections conducted at least once a year. The appearance of the product should be
visually checked to see if there is any damage, and if there is scale caused by measure objects, it
should be removed for the smooth operation of the float. The M-100R can simply be inspected
using a Digital Multimeter as follows.
■
Sensor Element Inspection
Separate the sensor lines connected to the M-100R
’
s terminals L, C, and H, and measure the resistance value
from the sensors.
Low and Com: resistance value of the current level
High and Com: entire levels
’
resistance value
–
current level
’
s resistance value
High and Low: entire levels
’
resistance value
■
Transmission Element Inspection
Without the disconnection of cable, current output can be checked using the Digital Multimeter between the
M-100R terminal ports T and –.
(refer to connection) in series and check if the current value that corresponds to the level is outputted.
Power Supply
Indicator
M-100R
Digital Multimeter
After checking the sensor parts, the wrong connection of H, C, and L is the cause of the product failure.
Sensor
Test Point
