Novar NOVAR-1xxx NRC Operating Manual - page 9
Novar-NRC
KMB systems
9
If the metering rate 2 control is enabled and any of the RCC-modes is set simultaneously, the
target PF is remote controlled by external NRC86 unit only when the metering rate 2 (tariff 2) just
active.In such case, the actual value of remote controlled PF with preceding „E“ character is
displayed in parameter 07 ( in the same way as in the parameter 01 when the metering rate 2 control
disabled). The parameter 01 has in such case its usual meaning, i.e. preset target PF value for tariff 1.
Thus, if the tariff 2 just inactive, the PF is controlled by the parameter 01 value and the remote
controlled target PF value is ignored.
The tariff2 value is evaluated in the usual way: either by state dig. input (1) or export (E).
2.3 Parameters 30 – Alarm Setting, 40 – Alarm Status
2.3.1 Alarm No. 6 – Undercurrent Alarm with Adjustable Limit or Alarm by Import with
Adjustable Limit and Fixed Outputs Release at Export
At standard Novar 1xxx controllers, the alarm No. 6 is controlled by THDI value.
At the Novar 1xxx NRC controllers, the alarm is not evaluated. The alarm No. 6 has one of following
meanings depending on its setting :
2.3.1.1 Undercurrent Alarm with Adjustable Limit
This is in fact enhanced undercurrent alarm. Behaviour of the alarm corresponds to the alarm No. 1
(thus, it is controlled by Ieff value); furthermore, the undercurrent limit value in “per mille”(ppt, range 0
÷ 200 ppt) of nominal current (5A/1A according parameter 13 setting) can be set in parameter 33.
For this alarm behaviour, the alarm No. 1 must be set in the same way as the alarm No. 6.
The limit value setup example : CT ratio (par. 12,13 ) is set to 500/5A. We intend to set the
undercurrent limit to 15A. Nominal current corresponds to the CT primary value, i.e. 500A, one ppt of
this is 0.5A. So we set the parametr 33 to 15 / 0.5 = 30.
2.3.1.2 Alarm by Import with Adjustable Limit and Fixed Outputs Release at Export
For this alarm functionality, the actuation function of the alarm No. 1 must be (unlike the function
described above) switched off (usual value
0
00
0
) and the actuation function of the alarm No. 6 must be
switched on (usual value
2
22
2
), simultaneously. Then :
•
The alarm No. 6 is triggered as soon as fifteen-minute average value of the active current
Iact is either positive (=import), or it is negative, but its absolute value is below the preset limit
in “per mille”(ppt, range 0 ÷ 200 ppt) of nominal current (5A/1A according parameter 13
setting) in parameter 33. During the check a hysteresis of +/-1mA is applied.
•
When the actuation is triggered all of the fixed sections are set to their preset states. The
controller goes on operation with the remaining ones. If all of the sections are fixed the power
factor control is suppressed.
•
As soon as the fifteen-minute average value of the active current Iact gets negative (=export)
and its absolute value exceeds the preset limit in the parameter 33, the alarm gets inactive.
At the same time, all of the sections preset as fixed ones are released for the control process,
i.e. they are considered as standard control sections.
•
This alarm function setting is indicated by slowly flashing decimal points at the sections
pressed as fixed at the parameter 26, that denotes their conditional behaviour