Filter
Top Products
216 Frequency outputs
Section 6: Meter operation Reference, Installation, and Operations Manual
June 2013 3-9000-743 Rev S
Frequency data content
Each frequency pair is configured via the FreqXContent data point to represent actual
(uncorrected) flow rate (0), standard (corrected) flow rate (1), average flow velocity (2), average
sound velocity (3), energy rate (4), or mass rate (5).
Frequency data flow direction
The frequency pair output represents the data content (selected via FreqXContent) when the
flow direction is in the selected direction (selected via FreqXDir). This option is available for all
frequency content options except average sound velocity. The options are:
• R
EVERSE (0): the selected data content is output when the flow is in the reverse direction.
• F
ORWARD (1): the selected data content is output when the flow is in the forward direction.
• A
BSOLUTE (2): the selected data content is output regardless of the flow direction.
• B
I-DIRECTIONAL (3): the selected data content is output on channel “A” only when the flow
is in the forward direction and on channel “B only when the flow is in the reverse direction.
Channel “B” operation on error
The frequency channel "B" can be configured to go to zero when the frequency data content is
invalid by setting the IsFreqXBZeroedOnErr data point to TRUE (1). Setting this data point to
FALSE (0) causes channel “B” to remain a copy of the “A” channel upon error. This option is
available for all frequency data flow direction options except bi-directional.
Channel “B” phase
The Frequency Channel “B” phase relative to the channel “A” phase is selectable (via the
FreqXBPhase data point) from the following options:
This option is available for all frequency data flow direction options except bi-directional.
This selection only matters if the device to which the frequency outputs are connected are
configured for Dual Pulse security and phase detection.
Maximum frequency
The maximum frequency is selectable as either 1000 Hz or 5000 Hz (via the
FreqXMaxFrequency data point). The Mark III meter can overrange the selected maximum
frequency up to 150% of the selected maximum frequency.
Table 6-11 FreqXB phase options
FreqXBPhase
Value
Flow
Direction
Phase Relationship
0
forward channel “B” lags channel “A” by 90 degrees
reverse channel “B” leads channel “A” by 90 degrees
1
forward channel “B” leads channel “A” by 90 degrees
reverse channel “B” lags channel “A” by 90 degrees