IRROMETER RSU-C User manual

Model RSU-C
INSTALLATION AND OPERATING INSTRUCTIONS
®
(1/21) #731
LITHO U.S.A.
Optimizing Irrigation . . .
Maximizing Conservation . . .
Worldwide Since 1951
WARRANTY: The IRROMETER COMPANY warrants its products against defective
workmanship or materials under normal use for one year from date of purchase. Defective parts
will be replaced at no charge for either labor or parts if returned to the manufacturer during the
warranty period. The seller’s or manufacturer’s only obligation shall be to replace the defective
part and neither seller nor manufacturer shall be liable for any injury, loss or damage, direct or
consequential, arising out of the use of or inability to use the product. This warranty does not
protect against abuse, shipping damage, neglect, tampering or vandalism, freezing or other
damage whether intentionally or inadvertently caused by the user.
®
1425 Palmyrita Ave., Riverside, CA 92507
951-682-9505 • FAX [phone]
[e-mail]
www.IRROMETER.com
The IRROMETER RSU-C is a pressure transducer sealed in a
stainless steel housing, which converts the 0 to 100 kPa tension
reading from the instrument into a 4-20mA current output. Any device
which can read a 4-20mA sensor and can supply between 9 and
36VDC can read the RSU-C.
For devices which cannot read a current loop but can read a voltage,
the RSU-V is available with a 0.5 to 4.5V output.
The calibration for the RSU-C is: (mA measured - 4)/0.16 = kPa
Note: Two wire insulated cable (suitable for direct burial) should be
used to connect RSU-C to Electronic Reading Device – #18 AWG
size (standard preferred)
RSU-C – Remote Sensing Tensiometer
— CAUTION —
Do Not Install by Hand
You must use a 1 5/16" wrench (24mm) for the transducer.

32
— WARNING —
Do Not use water containing chlorine or sulfur (distilled preferred)
or cleaners containing chlorine or sulfur with the RSU-C.
When de-airing the transducer equipped IRROMETER (Model RSU-C)
care must be taken to release the vacuum slowly. A sudden release
of the vacuum could cause damage to the pressure transducer,
rendering the instrument inoperable. Transducers damaged by
sudden release of the vacuum are unrepairable and would require
complete replacement of the entire transducer assembly.
Reading the RSU-C with a Digital Meter
VACUUM
0 kPa
50 kPa
100 kPa
RSU-C (Standard Instruments)
The DVM shows 4mA
The DVM shows 12mA
The DVM shows 20mA