Sigma Controls MYRIAD DPC Instruction Manual page 24

If D.C. voltage is present, reconnect the negative wire of the supply and insert a millimeter
between the positive wires. The loop should provide a signal between 4 and 20 MA. If no
current is present or the current exceeds 20MA consult the level instrument supplier.
If D.C. voltage is not present, check the user supplied power supply or if using the Myriad
supply measure across terminals 24VDC and A/C. If no 24VDC is present consult factory. If
24VDC is present check field wiring between the Myriad and the field device and recheck
'SCALE' functions to insure correct setup.
Unit appears to be functioning but does not bring on pumps or alarms. From 'MENU 2' scroll
to 'DIAG' and press enter:
DIAGNOSTIC SCREEN
Digital Input
& Outputs
The diagnostic screen provides information about the current status of inputs and outputs and
provides valuable information to aid in trouble shooting.
The screen shows the status of the 'RAW' analog input 1 and output 1 values. These raw values
are approximately the input and output range in the selected input value; as shown, the input is
20.00 MA and the output is 20.00 MA. These values can provide help in determining if the
Myriad DPC is receiving the correct analog input.
The next indicators are the digital input/output status. Any active (ON) DO/DI is indicated by an
active, black, block above its respective number.
The input/outputs are as follows:
AI
Raw input from level sensor (4AI)
'Raw' Analog In
DO/DI
ANALOG
'Raw' Analog Out
DO/DI
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