beautypg.com

Measurement Computing TempScan/1100 User Manual

Page 70

background image

4-12 System Configuration

879596

TempScan / MultiScan User's Manual

To Compute the MultiScan/1200 Scan Interval

To compute the time interval for the MultiScan/1200 to acquire one scan, use the following formulas:
For a 60-Hz Line Cycle: Scan Interval equals:

Is-m = Cv x (Wv + 12) x R3

For a50-Hz Line Cycle: Scan Interval equals:

Is-m = Cv x (Wv + 12) x R4

Where:

Is-m

= Scan Interval for the MultiScan/1200, milliseconds.

Cv

= Channels, variable number of configured channels in the scan.

Wv

= Sampling Weight, variable number of samples per channel.

R3

= Sampling Rate, constant of 0.52083 milliseconds (per sample) for a 60-Hz line cycle.

R4

= Sampling Rate, constant of 0.62500 milliseconds (per sample) for a 50-Hz line cycle.

For example, if 148 channels are configured, the disposition of these channels will not be a factor. Using
the scan interval formula for a MultiScan/1200 system with a 60-Hz line cycle, if the system is configured
to take 1 sample per channel, gives:

Is-m = 148 x (1 + 12) x 0.52083 millisec.
Is-m = 148 x 13 x 0.52083 millisec = 1002 millisec = 1.002 seconds.

Meanwhile, the following table shows how the fast mode scan rate varies when the number of configured
channels increases where these MultiScan/1200 channels are all adjacent to each other, and are using the
default sampling weight of 32 samples per channel.

Variations of the MultiScan/1200 Fast Mode Scan Rate

Number of

Number of

Scan Rate (Hz)

12-Channel

Selected

60-Hertz Line Cycle

50-Hertz Line Cycle

Blocks

Channels

Hertz

seconds

Hertz

seconds

1

12

3.636 0.275 3.030 0.330

2

24

1.818 0.550 1.515 0.660

3

36

1.212 0.825 1.010 0.990

4

48

0.909 1.100 0.758 1.320

5

60

0.727 1.375 0.606 1.650

… … … …

10

120

0.3636 2.750 0.3030 3.300

… … … …

50

600

0.0727 13.750 0.0606 16.500

… … … …

60

720

0.0606 16.500 0.0505 19.800

61

732

0.0596 16.775 0.0497 20.130

62

744

0.0587 17.050 0.0489 20.460

Note: (1) The number of selected channels refer to configured channels which are all adjacent to

each other. (2) These values were obtained from the above MultiScan/1200 scan interval
equations.


This manual is related to the following products: