Milltronics OCM II PL-269, Instruction Manual

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TEMPERATURE SENSOR
Refer to figures 4 & 8 for mounting and wiring.
VELOCITY SENSOR (optional/not by Milltronics)
Connect the velocity sensor output to terminals 16,17 & 18 of TB-1 on the OCM II motherboard.
For virtually any cross sectional channel shape, a velocity sensor can be used in combination with the level from
the transducer to calculate the flowrate.
The OCM II is factory set to accept a standard 1 to 5 volt signal from the velocity sensor (for a 4-20 mA signal,
a 250 ohm 1/4 W resistor must be installed across TB1-16,17). However, the output from a velocity sensor within
a range of 0 to 10 volts and having a minimum span of 2.5 volts may be used.
Refer to Appendix B for instructions on re-scaling the input for velocity sensors.
INTERCONNECTION
All wiring must be performed in conjunction with approved conduit, boxes
and fittings and to procedures in accordance with all governing regulations.
Ensure the 9.53 Kohm load resistor across TB1-13, 14 is removed prior to temperature sensor connection.
If the optional data transfer link to a computer is used, the baud rate of the OCM II and computer must be the
same. This also applies to the serial printer if it is used. Set switch SW1 as follows:
SW1 POSITION BAUD RATE
(toggle down at)
1 - 9600
2 - 2400
3 - 1200
4 - 300
For Baud rates of 75, 150, 600 or 4800, set all SW1 toggles down at "open" and solder a jumper (J4, J5, J6 or
J7) onto the main board. Connect the communication cable to TB1-25 to 30.
Refer to figure 2 and Appendix C, Hardware Consideration.
Make sure that jumpers are properly set for standard 115 V AC or 230 V AC or special 100 V AC or 200 V AC
operation. Refer to figure 2 or see diagram on motherboard.
The main fuse must be installed. When making the power connection ensure that wires are securely fastened to
the proper terminals.
Do not operate with ground (earthing) wire disconnected.
Flip the power switch located at the lower edge of the motherboard "ON" and re-install the front panel. The unit
is now ready for start up.
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91/02/14
PL-269 3 – 2