User Guide

(8): The hold mode is never enabled by the control timing if

the “hold time start” is the same as the “hold time end”.

Items “C.41” and “C.42” apply to all days. The hold mode

can be enabled all day by using items “C.51” through “C.57”.

(9): See the “Temperature compensation” subsection for more

details on how the Automatic temperature compensation and

Manual temperature compensation work.

(10): Whenever the pH/ORP selection item is changed from

pH into ORP or vice versa all of the calibration and setup

data regarding pH (when changing to ORP) or ORP (when

changing to pH) are kept. They are automatically restored if

the controlled parameter is changed back later. The follow-

ing setup items cannot vary when changing from pH to ORP

or vice versa (because they are items strictly related to the

instrument and not to the controlled magnitude): Factory ID,

Process ID alias RS485 address, Calibration/hold password,

General password, Baud rate, Modem calls answer enable,

Cellular/PC connection items, Hardware identifier and RTC

date and time. For proper operation while working with the

Digital Transmitter, this item must be equal to the correspon-

dent one in the Digital Transmitter. If the two values do not

coincide a “Digital Transmitter error” is generated.

(11): A life check error is generated if the pH reading does not

vary for more than ±0.10 pH within the time selected through

the “life check time” item (pH controller) or mV reading for

more than ±10 mV within the same time (ORP controller).

(12): When the Digital transmitter (HI 504910) is used, the

temperature is measured by the transmitter along with pH

(pH controller), or ORP (ORP controller). These measure-

ments are sent to the Process Controller. The calibration data

set for the Digital Transmitter is kept within the transmitter and

thus it is separated from the BNC set. This means that the

calibration slope and offset and the other GLP data are au-

tomatically switched from the BNC set to the Digital Transmit-

ter set and vice versa when the measurement input is switched

from “Prob” to “trAn” respectively. For example, if the user

was using a pH electrode connected to the BNC, and at a

later time he starts using the transmitter, and after that the

measurement input selection is reverted back to “Prob”, it is

not necessary to calibrate the pH electrode again.