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200/202 Series Flowmeters and Controllers Instruction Manual
EAR99 Technology Subject to Restrictions Contained on the Cover Page
Page 15 of 27
2.5.2.
Unipolar (24 VDC) Power Supply to Unipolar Connections
Refer to the diagram below when connecting 24 Volt units. Connect the positive lead of the power supply
to pin 7 of the DE-9 connector and negative lead to pin 4. The supply input is diode protected such that
reversing the input polarity will not damage the instrument. The power supply is galvanically isolated
from all other pins. A pinout is also given to show the signals available to the user and the signals given
and used by the power supply (Not all signals from the PCB are used by Hastings supplies). A special
cable is available to connect the 9-pin unipolar power option 200 Series instruments to ±15VDC power
supplies.
2.5.3.
General Connection Notes
Pin 7 of the DA-15 (15 Volt), and pin 9 of the DE-9 (24 Volt) are the case grounds. Case should be
connected to the cable shield if available and to the AC ground to the power supply. Pin 6 of the DA-15
(15 Volt), and pin 2 of the DE-9 (24 Volt) is the output signal from the flow controller. This output will be
0
–
5 VDC/(4 - 20 mA), 5 VDC/20 mA being 100% of rated or full flow. Pin 14 of the DA-15 (15 Volt), and
pin 3 of the DE-9 (24 Volt) is the command input. This should be a 0
–
5 VDC or (4 - 20 mA) signal and
must be free of spikes or other electrical noise, as these will generate false flow commands that the
controller would attempt to adjust for. Pin 15 of the DA-15 (15 Volt), and pin 1 of the DE-9 (24 Volt) is a
regulated 5 VDC output (±0.005 V) reference which is occasionally used as a full-scale command. If a
valve override switch is not desired, the unit is now ready for use.
If an override switch is desired, connect the center pin of a single pole, three-position switch with the
center off position to pin 8 of the DA-15 (15 Volt), pin 6 of the DE-9 (24 Volt). Connect a voltage source
>10 VDC to one end of the switch, and negative voltage to the other end. This will result in the valve
being full open when the positive voltage is supplied to the override pin, closed when the negative
voltage is supplied, and auto-control when the valve override pin floats (OPEN-AUTO-CLOSE). This setup
will be adequate for most purposes, but there will be a small delay for capacitors to charge between
switch operation and control override.
WARNING:
Care must be taken to avoid any high voltages that may be present when
dealing with power supplies.
Pin #
PCB Signal
Hastings Power
Supply
1
5V Reference
Not used
2
Signal Output
(0-5V or 4-
20mA)
6
3
Set Point (0-5V
or 4-20mA)
14
4
Power Common
9
5
Valve Voltage
Not used
6
Control Valve
Override
8
7
Power Input (11
to 36 VDC)
11
8
Signal Common
5
9
Case Ground
7