Siemens SG8158-00 manual Active Set, Parameter Sets

Control & Communications

Figure 6.6 Current Balance Threshold

Failure of this check will cause an event Current Balance Error. This event can activate an output contact.

The pickup value (3422) for the current balance check depends on the secondary phase CT rating and the value is in secondary amperes. For 5 A CTs, the value ranges from

0.5to 5.0 A; and the value for 1 A CTs ranges from 0.1 to

1.0A. Both values can be set in steps of 0.1 A. If one of the three phase currents is above the preset threshold, the mon- itoring function is activated.

The current balance factor indicates the amount of unbal- ance tolerated before the function generates an alarm (3424). This factor is provided to compensate for differences between primary CTs. It ranges from 0.1 to 0.95 and can be set in steps of 0.01.

6.11 Parameter Sets

The ISGS relay can be programmed to operate with either of two parameter sets—set A or set B. Separate parameter sets are programmed to satisfy separate user defined condi- tions, such as seasonal considerations or special operating periods. For example, set A may be used for protective set- tings used in the summertime, whereas set B might com- prise the settings appropriate to winter, when lower ambient temperatures could allow higher loading than in the summer. Alternatively, set A might be configured for normal production periods, with set B reserved for construction or periodic shutdown periods. The choice of two separate parameter sets prevents the need to reconfigure the relay when condi- tions change and different parameter settings are desired.

Figure 6.2 shows the use of these parameter sets. The val- ues in set A or B may be chosen as the active set, and are thus put in the relay’s memory for easy access. The default set includes all the factory default values and these values are stored in long-term memory.

		Default
			Set
			Copy
	Set A			Set B
Save		Activate		Save

Active

Set

Figure 6.2 Parameter Set Actions

7101	Parameter Set
Address	Parameter	Description
7101	Active Set	Displays active parameter set
		(A or B)
7103	Activation	Activate set A or set B
7104	Copy Default to A	Copy default set to set A
7105	Copy Default to B	Copy default set to set B
7106	Copy A to B	Copy set A to set B
7107	Copy B to A	Copy set B to set A

6

Only certain protective function parameters have two set- tings. All A settings are grouped under parameter set A, and all B settings are grouped under parameter set B. Each parameter set automatically includes all the regular parame- ters that can be programmed to only one setting at a time

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