GE EPM 9650/9800 manual Power Quality Cbema Log Format, Format Range Description

6.8: Power Quality (CBEMA) Log Format

PQ (CBEMA) Log Format: The PQ (CBEMA) Log records in response to surges and sags of programmed High Speed Limit Triggers on enabled High Speed channels. The information it provides allows the calculation of duration and magnitude of the surges and sags, as well as information for locating the start and end of the surge or sag in the Waveform Captures.

Record Format: A Record contains 128 Bytes.

•The first eight bytes in each record is the Starting Time Stamp, representing the time of the last sample of first cycle of the surge or sag. The format of the Time Stamp is:

Byte		Format	Range	Description
	0	binary	0 – 99	century
1		binary	0 – 99	year
2		binary	1 – 12	month
3		binary	1 – 31	day
4		binary	0 – 23	hour
5		binary	0 – 59	minute
6		binary	0 – 59	second
7		binary	0 – 100	centisecond

Note: This log does not record records during Test Mode.

•The next byte is the millisecond value for the Starting Time Stamp, a binary value in the range of 0 – 9.

•The next four bytes are a bitmap of the States of the High Speed Limits after the triggering cycle. These bits report the true state of all the limits, regardless of PQ Enable settings.

						Table 6.10: Above Limits
							Above Limit
15	14	13	12	11	10	9	8	7	6	5	4	3	2	1	0
VAN	VBN	VCN	VAUX	IA	IB	IC	IAUX	IN	VAB	VBC	VCA	_	_	_	_

The first two bytes are for the above limits, shown in the following order:

The other two bytes are for the below limits, and are in the same order as shown in Table 6.10 above.

There are currently five hookups available where the following high speed limits are computable in each:

3	Element Wye	VAN, VBN, VCN, IA, IB, IC, IAUX
3	CT Delta	IA, IB, IC, IAUX, VAB, VBC, VCA
2	CT Delta	IA, IC, IAUX, VAB, VBC, VCA
2-1/2 Element Wye		VAN, VCN, IA, IB, IC, IAUX
Broken Delta		VAN, VBN, VCN, IA, IB, IC, IAUX, VAB, VBC, VCA

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