Pulse Comparison; Pulse Generator Connection - Honeywell Elster EK280 Applications Manual

EK280

4.5 Pulse comparison

Pulse generator errors can be detected early using pulse comparison.
In principle, any two pulses may be compared. The process for securing the custody transfer measurement
using a pulse generator on input 2 to monitor the pulse generator on input 1, is described here.
i
The pulse generator used for pulse comparison must have the same pulse value (cp value)!
With regard to the "HF pulse input with automatic conversion" described in chapter 4.4 the calibration lock
must not be open and the input 2 terminal must not be sealed, as they are not used in custody transfer
measurement. This means also that, should the pulse generator on input 1 fail, the volume will not be
incremented further, but instead a warning will be given.
If the "maximum number of disturbance pulses" set in the "pulse window per disturbance pulses" is
exceeded
the message "I2-Imp.vgl." momentary status "Stat" and status register "SReg" is entered,
"W" flashes in the display.
An impulse window is also calculated, to allow a certain number of error pulses, below which the message is
removed from the momentary status. Until the status register is cleared by the user the message and the "W"
in the display will remain permanently (unless another warning is generated).
The status message can then be used, for example to create an archive entry or to switch an output.

4.5.1 Pulse generator connection

Danger!
For EK280 with integrated power supply, the mains voltage must be switched off before
opening the housing, ensure it is not turned back on and verify that there is no voltage.
Pulse Generator
LF
(Reed contact)
Connect the low frequency pulse generator (LF reed contact) of the gas meter used for the custody
transfer measurement to terminal "DE1" of the EK280.
Connect the second low frequency pulse generator (LF reed contact) to terminal "DE2".
Application Manual
DE1 DE2
+ - + -
Pulse Generator
1 2
LF
(Reed contact)
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