Scan Mode, High/Low Channel Mode | Omega Vehicle Security DPS3300

Scan Mode

When setup for scan mode, individual channels are displayed for a programmed period of time. At the end of that time period the, display automatically switches to the next channel. For ease of reading, the display first shows the channel number (Format: 'CHANEL 1') and then the process variable along with the programmed three digit engineering units e.g. 23.45 PSI.

Display time for each channel is programmable from 1-999 seconds (16.65 min.). This is useful for adjusting display time to a rate which is consistent with the type of process being monitored. Scan time for each channel is independent of display time. This permits programming long display times without losing track of the process on other channels.

The display can also be put in a hold mode by pushing the SCN/HLD key. When this key is pushed, the display will briefly show 'HOLd' after which the display will stop on the channel it was

indicating. Putting the unit in HOLD mode inhibits automatic display scanning and shows only one particular channel. While the display is held on one channel, internally all the enabled channels are continuously scanned for rate, difference, limits and other parameters. Also, during HOLD mode the unit will periodically flash the display 'Cx HOLd' ( x=channel # on hold) to indicate the status of the display mode. If an attempt is made to hold on a channel that has been turned off then the unit will indicate so by displaying in the format 'CHx OFF' ( x=channel # off).

To select another channel for display during hold mode, push the CH. SEL key. Each push will increment the channel number. The display will first show the channel number (e.g. 'CHANEL 2' for channel # 2) followed by the process

variable in the form '0.123 PSI'. When channel selection is initiated using the CH. SEL key, the unit starts with channel #1 and steps thru to channel #7 with each push of the key.

To take the unit out of HOLD mode and back into SCAN mode, push the SCN/HLD key. The display will briefly show 'SCAN' and then start scanning the channels.

High/Low Channel Mode

DPS3300 Series compares all the channels against each other and constantly tracks the channel with the highest and lowest process value. On push of a key, the channel number and the value of process variable can be displayed. Also, during SYS Setup, the unit can be programmed so that instead of scanning all the channels it will only display the channel with highest or lowest process variable. As the process changes, the display automatically switches over to the channel with the highest (or lowest, if so programmed) reading. This is a very useful function for applications involving multi-point monitoring of temperature in a single process. For example, this feature can be used to find hot spots in a kiln. During high or low

channel scan mode the display will periodically flash 'HI CHAN' or 'LO CHAN' (depending upon the selected mode) to indicate the status of the display mode.

To display high and low channel from any other display mode simply push the HI/LO key. Pushing this key once will first display 'HI CHAN' and then the channel number and the process value will be displayed in the format 'C2 1234'. The second push on the HI/LO key will first show 'LO CHAN' in the display window, and then the channel with the lowest process value will be displayed.

NOTE: (i) The second push, to display low channel, must be initiated before the display reverts back to the normal display mode.

(ii)If a channel is selected using the CH. SEL key prior to the push on the HI/LO key, then instead of displaying high and low channels, the unit will display high and low peaks of the active channel. Therefore, if it is desired to display high and low channels and not the peaks, do not select a channel before pushing the HI/LO key.

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