Tare' Setup; Limits' Setup; Deadband' Setup; Relay Latched/Non-Latched Mode' Setup - Omega Engineering DP3300 Series User Manual

Programmable dual channel monitor
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DP3300 Series User's Manual
suppose a flow transducer outputs a 0.130Vdc to 5.000Vdc signal which corresponds to a flow rate of 0 to 40 gal./min. Then to
make the 0.130Vdc correspond to a display of 0, set OFFSET =0.130.
NOTE: If the input type is CURRENT, the Offset value is entered in milliamps.
If the input type is VOLTAGE, the Offset value is entered in millivolts.
After pushing SETUP key at the completion of Setup For Low Scale, the display will briefly read 'OFFSEt', and then show the
present Offset value. The active digit will be flashing. Use ^v key (as described in Setup For High Scale) to enter a desired
OFFSET value. After the desired OFFSET value is displayed, push the SETUP key to go to the next step.

'Tare' Setup

After setting a channel's OFFSET value, the next parameter to be set is channel TARE. TARE is used if it is necessary to always
subtract a value from a reading prior to displaying that reading. For example, suppose a pressure transducer always includes
atmospheric pressure of 15 psi, and you only wish to display pressure differential from atmospheric (a gage reading of 19psi is to
be displayed as 4psi). To do this, enter the number you want subtracted from the measurement prior to displaying it.
The display will first show 'tARE' after which current TARE value will be displayed. Use ^v key (ref. Setup For High Scale) to
set the desired TARE number. Once the desired TARE value is displayed, push the SETUP key to enter that value and go to the
next step.

'Limits' Setup

DP3300 uses LIMIT parameter to determine when to activate output signal for a specific channel. When a reading exceeds
LIMIT value , then the output for that limit is activated. When a channel reading drops below the LIMIT setting by an amount
equal to the DEADBAND setting, then the channel's output is de-activated.
The display will first show 'CHx Lt1' (where 'x' is the channel number) following which the LIMIT value will be displayed.
Use ^v key (ref. Setup For High Scale) to set a desired value. Once the desired LIMIT value is displayed, push SETUP key to
enter that value and go on to setting up limit 2. After limit 2 (which is setup just like limit1), limit 3 for the channel will be setup.

'Deadband' Setup

After setting a channel's limits, the next parameter to be set is the channel's output relay DEADBAND. This parameter is used to
eliminate relay "chatter" as a signal hovers around its LIMIT value. When channel reading drops below the LIMIT setting by an
amount equal to DEADBAND setting, then that particular limit output is de-activated. The minimum value of DEADBAND is 2.
The display will first show 'dEAd bd' after which the present DEADBAND value will be displayed. Use ^v key (ref. Setup For
High Scale) to set the desired DEADBAND value. Push SETUP key after programming DEADBAND value.

'Relay Latched/Non-Latched Mode' Setup

In Latched mode the relay is activated when its LIMIT value is exceeded and stays activated until the operator manually resets the
relay. To manually reset a relay on channel 1 or 2, first select the channel by pushing the CH. SEL. Then push the DATA key
until the desired limit number for the particular channel comes up on the display e.g. CH2 LT3 (Channel 2, limit number 3).
While keeping the DATA key pressed, simultaneously press the RESET key. This will reset the respective limit relay (NOTE:
Process reading should be below the limit value for the relay to reset. Otherwise, pushing of the keys will be ignored)
In Non-latched mode the relay is activated when its LIMIT value is exceeded. The relay is deactivated when the channel readings
drop below the LIMIT value by the DEADBAND setting.
The display will show 'NON LCH' for Non-Latch mode, or 'LAtCH' for Latch mode. Use ^v key to toggle between settings.
Once the desired setting is displayed, push SETUP key to enter that value and go to the next step.

'Relay Normally Open/Closed' Setup

After setting DEADBAND, the next parameter determines whether channel's output relays will operate as "Normally Open" or as
"Normally Closed". The relay itself is a Single Pole Single Throw (SPST) relay.
When this parameter is set for "Normally Open", the relay contacts are open when reading is below LIMIT, and closes when the
channel reading exceeds its LIMIT value.
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