Hach POLYMETRON 8810, User Manual

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4.5.3 Input/Output connections
D A N G E R
Electrocution hazard. Always make sure the analyzer is turned off and power is disconnected
before making any of the connections in this section.
W A R N I N G
To conform with security standards and to respect the EMC compliancy of the analyzer, follow the
procedures defined in
Wiring procedures and cable preparation on page 12 for all connections to
the electronic unit of the analyzer.
The electronic unit ( No. 11 in Figure 3 on page 9) must be opened from the rear to make
these connections. Unscrew the four screws holding the unit rear panel and gently swing
open from left to right. Refer to
Figure 8 for terminal locations and the following tables for
the functions.
Note: The terminal connectors diagram is also physically located on the rear of the electronic unit.
Figure 8 Terminal connectors
Table 1 Microprocessor board
Terminal Description
X1 - X4
Relay configurations K5 - K8
• 2-3: Dry contact relay
• 1-2 and 3-4: 24 VDC
X5
Serial interface
• 1-2: RS 232
• 2-3: RS 485
Installation
18