Xylem H-3553 User Manual

Page 25

Setup & Operation

H-3553 Combo Bubbler setup menu

sDI-12 Interface

P – Advanced Options

Command: aXWILn.nn!

Response: a0021

advanced Options menu

Command: aXRIL!

F – 4-20 mA Output

Response: a0011

Command: aD0!

4-20 ma Output setup menu

Response: a + n.nn

N – Min Stage: x.xx
Enter 4 - 20mA Min Stage [ n.nn ]

Table 4-17: Change the H-3553 4-20 Milliamp Min Stage

4-20 Milliamp Max Stage

The 4-20 milliamp max stage value should be the highest the stage gets at the installed site. When the stage
equals this value or greater the 4-20 milliamp output will be 20.0 milliamps, the max.

The H-3553 4-20 milliamp max stage default value is set to 20. There is no limit to this value, but keep in mind
that the smaller the overall range of the 4-20 stage scalar, which is the min to the max stage, the more accurate
the 4-20 milliamp output will be. To change the 4-20 milliamp max stage using the RS-232 main menu, press
the ‘P’ key to enter the “Advanced Options” menu and then press the ‘F’ key to enter the “4-20mA Output
Setup” menu. Then press the ‘X’ key in this menu, enter in the new “Max Stage ” value and press the ‘Enter’ key.

To change the H-3553 4-20 milliamp max stage using the SDI-12 interface, send the “aXWIHn.nn!” SDI-12
extended command. The response should be “a0021”, which means that it could take 2 seconds to complete
the command and then it will put 1 data value in the buffer. To check the new 4-20 milliamp max stage, send
“aXRIH!” command and wait the responded time. Then send the “aD0!” command to read back the new
written 4-20 milliamp max stage. Note Table 4-18, the ‘a’ is the current SDI-12 address of the H-3553 and the
‘x.xx’ is the current 4-20 milliamp max stage and the ‘n.nn’ is the desired 4-20 milliamp max stage.