Basler BE1-CDS220, Инструкция по эксплуатации

Страница: 134 / 476

6-16 Reporting and Alarm Functions BE1-CDS220
Number of Through Faults Monitoring Function
This function monitors the SG-TRIGGER pickup logic expression. It increments the count in the
operations counter register each time that the SG-TRIGGER pickup logic expression is true and returns to
false. For more information on this function and the SG-TRIGGER pickup expression, see the illustration
and paragraphs later in this section on Fault Reporting.
Retrieving Through Fault Operation Counter Information
The current value of the through-fault operations counter register can be read from HMI Screen 4.5.1,
\REPRT\XFORM\STATUS. Pressing the Edit key allows the user to enter a number into the register to
preset it to a value if desired. Write access to the reports functional area must be gained to edit this value
at the HMI. The current value of the breaker operations counter can also be read or preset from the ASCII
command interface using the RT-TFCNTR (report transformer, through-fault counter) command.
RT-TFCNTR Command
Purpose:
Read/Set Transformer Through Fault Counter
Syntax: RT-TFCNTR[={#operations}]
Comments: # through faults = number of through faults recorded (0-99999).
RT-TFCNTR Command Example:
Example 1. Set relay through-faults counter at 65 through faults.
>RT-TFCNTR=65
The through fault counter can be monitored to give an alarm when the value exceeds a threshold. See
Transformer Alarms in this section for more information on this feature.
Transformer Duty Monitoring
The transformer duty monitoring function accumulates the maximum current in each phase of the
transformer when a through fault occurs. A through fault is defined as whenever the pickup expression set
with the SG-TRIGGER command is true.
Every time the pickup expression in the SG-TRIGGER command is true, the transformer duty monitoring
function updates two sets of registers for each phase of the transformer. (Only the CT selected by the
transformer duty monitoring function (ST-DUTY) is monitored.) In the accumulated
I*t
Duty registers,
the function adds the maximum measured current in primary-ampere seconds. In the accumulated
I2*t
Duty registers, the function adds the maximum measured current squared in primary-ampere seconds.
The
t
is calculated from the time the pickup expression is TRUE. The user selects which of the six sets of
duty registers are reported and monitored by the function when setting up the mode setting in ST-DUTY.
The value in each set of duty registers is calculated and stored in primary ampere seconds or primary-
amperes squared seconds as appropriate. This value is reported, however, as a percent of maximum.
The user sets the value that the relay will use for 100% duty (DMAX). The value set for maximum duty is
used directly for reporting the accumulated
I*t
Duty registers or
I2*t
Duty registers.
When testing the relay by injecting currents into the relay, the values in the duty registers should be read
and recorded prior to the start of testing. Once testing is complete and the relay is returned to service, the
registers should be reset to the original pre-test values. A block accumulation logic input may be used
when testing so that simulated transformer duty is not added to the duty registers. The BLKTXFMR logic
function is an OR logic term (e.g., IN1 or VO7) which blocks the transformer monitoring logic when TRUE
(1). BLKTXFMR may be set to zero to disable blocking. When transformer monitoring is blocked (logic
expression is equal to 1), transformer through faults are not counted or accumulated. It should be noted
that even though a BESTlogic logic expression is used to make this setting, this setting is not included in
the section on BESTlogic settings.
Setting the Transformer Duty Monitoring Function
The transformer monitoring function can be set from BESTCOMS (Figure 6-7). Pull down the Screens
menu and select Reporting and Alarms. Select the Transformer Monitoring tab. Alternately, settings can
be made using the ASCII command ST-DUTY (setting transformer, duty) command or the HMI using
Screen 6.6.1, \SETUP\XFRMR\DUTY. This function selects the transformer CT to be monitored that also
affects the transformer alarm function (SA-TX). Table 6-8 lists the settings for the transformer duty
monitoring function.