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CHAPTER 6:
Service
Model 648 Electromagnet Power Supply
6.11 Connector
and Cable
Definitions
All non-power electrical connections to the rear of the Model 648 are detailed in this
section.
6.11.1 Analog I/O
Connector
The analog I/O connector provides the connections for the external programming
voltage as well as analog representations of the current and voltage output levels.
Although these inputs/outputs are electronically balanced to minimize ground loops,
the common-mode voltage should not exceed 5 V on the outputs and 2 V on the input.
Analog I/O connector
Model 648 analog/output connector
Pin
Name
Pin
Name
1
NC
9
NC
2
Chassis–common
10
Chassis–common
3
Current program —
11
Current p
4
Chassis–common
12
Chassis–common
5
Voltage monitor —
13
Voltage m
6
Chassis–common
14
Chassis–common
7
Current monitor —
15
Current m
8
Chassis–common
6.11.2 Magnet Water
Connector
The magnet water connector provides the means to connect a water control valve
(24 VAC) and an associated water flow switch (closed during flow) to protect the
magnet from loss of water flow. Pins 1 & 2 must be closed for normal operation. Pins 3
& 4 supply 24 VAC at 1 A for operation of a water control valve. See TABLE 6-5 for the
magnet connector details.
Magnet water connector
FIGURE 6-6
TABLE 6-4
FIGURE 6-7
