Omega CMDP Series, User Manual

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6
PCB blue connector:
Pin 3 (+) 4-20mA output
Pin 4 Ground
Pin 5 (+) 4-20mA output
Pin 6 (-) common for 4-20mA outputs
Pin 7 (-) Air temperature probe
Pin 8 (-) Air temperature probe
Pin 9 (+) Air temperature probe
Pin 10 (+) Air temperature probe
Pin 11 Return
Pin 12 24Vdc (@1A)
Protocol setup to run or program the CMDP.
No special software is needed. User can use either the TeraTerm program or the HyperTerminal program on their PC.
Connect the RS232 connection from the Dew Tran and using a USB converter connect to your PC.
Protocol configuration: Baud rate 19.2K, 8 Bits, 1 stop Bit, No parity
To access the menu, hit the “esc”
The Cap lock key must be on when selecting commands.
Calibrating Current Outputs
There are 2 methods for calibrating the 4-20 mA. outputs. Method 1 uses a digital ammeter, capable of 1 uA.
Resolution. The second method uses high precision (.005%) Resistor(s), In range of 10 – 750 ohms. The
factory Calibration is done using 100.00 ohm resistors.
for output 1, connect Ammeter across BLACK Wire and RETURN. From normal operation, enter following
keystrokes:
<ESC> <C>hange <O>utputs <C>alibrate <C>urrent.
at the “Sense Resistor Value (Y/N) OHMS?” Prompt, enter <N>
Enter<1> for Current output 1. The prompt “4 mA. = ?, enter the value displayed on Ammeter, as mA’s
Continue for the next 2 prompts (12 mA. and 20 mA.)
the prompt “4 mA. = 1XXXX” is displayed, check Ammeter for 4.00 mA. reading. Press <CR> to sequence (8,
12, 16 ,20 mA.) Values, with corresponding Ammeter Readings. If calibrated values good, at “Save Calibration
(Y/N)?, enter<Y>.