ABB COMMANDER 1900 Series, Руководство пользователя

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4 ADVANCED CONFIGURATION LEVEL
4.1 Introduction to Totalization
Information.
• One 8-digit totalizer per channel.
• Count up or count down.
• Count rates – from 0.001 to 100.0 counts/second.
• External counter pulse – can be used to energize relays or digital outputs (a maximum of 4 pulses per second are
generated).
• Wrap function – with external wrap pulse used to energize relays or digital outputs.
• Programmable preset and predetermined count values – for (batch) flow total.
• Adjustable cut-off values.
• Operator level reset and stop/go.
• Digital signal reset and stop/go.
The totalizer option provides indication and recording of flow rates from input signals with linear, square law or power law
characteristics. Totalization is available for each channel and may be switched on or off as required.
The flow total for any channel can be viewed on the digital display and reset using faceplate 1. An additional internal ‘Secure’ total
is also provided which can only be reset after gaining access to the
ADVANCED CONFIGURATION LEVEL
.
External counters with their own power supplies can be driven using 4 relay and digital output module options.
4.1.1 Converting the Engineering Flow Rate – Example A and B
To calculate the count rate high the engineering flow rate high must first be converted into units per second. The engineering range
(display range) value is limited to
9999
. In some circumstances the engineering flow rate high value may be greater than
9999
and the engineering range must therefore be scaled. In the calculation of units/second the actual engineering flow rate high value
must be used.
Units/Second =
Actual Engineering Flow Rate High
Engineering Range Units (in seconds)
4.1.2 Calculating the Count Rate High – Example A and B
The count rate high is calculated from the units per second and the counter factor. The counter factor is the value of the least
significant digit shown on the totalizer display (viewed in
Totals Page
,
OPERATOR LEVEL
). The count rate high must be within the
limits of 100.0 to 0.001 pulses per second. If the pulse rate value falls outside these limits, the counter factor (the least significant
digit) must be increased – see Example B.
Count Rate High =
• Totalization
units/second
counter factor
Must be within the limits of 100.0 to 0.001 pulse per second