Hanna Instruments HI 943500A - Manual (Page 12)

23 22
• Set
Dosing pumps or other control equipment may be connected to the
"SET" (Max. 2A, 240 V) terminals. These contacts act only as a
"dry" switch allowing electrical continuity, not as a power supply.
• Alarm Contacts
During normal operation these ter-
minals remain closed.
If the measured conductivity level
is not within the tolerance of the
set value, the alarm contact is
open. These contacts act only as a
switch. See also page 29.
REAR CONNECTIONS FOR HI 943500
• Power Connection Terminals
4-screw-terminal-strip for connec-
tion to a 3-wire power cable ac-
cording to the indicated voltage
(115 or 230 V).
• DIN connector socket
For connection to the
HI 7638 conductivity
probe.
• + mA output -
The first and the second
terminals are the output
terminals for connection to
a recorder or other control
equipment. The output cur-
rent varies from 4 to 20
mA and is proportional to
the measured conductivity
value.
• Set Select
These contacts permit the
activation of the Set Contact relay when the measured value is
lower (connected terminals) or higher (open terminals) than the
user's set value. See also page 28.