Spectrum Controls 1734sc-OE2CIH - Manual (Page 51)

Chapter 4: OE2CIH and HART 4-15
User’s Manual Pub. 0300272-01 Rev. A.0
HART STATUS BYTE 3: Extended Device Status
This is the first byte returned with Command 9 by HART revision 6 and 7 devices. It is
not used and always zero (0) for HART revision 5 devices:
Bit Mask Definition
0×04 = Critical Power Failure
0×02 = Device Variable Alert
0×01 = Maintenance Required
Output Instance (102)
Table 4-10 Output Assembly
Instance: ID: Description: Total Size:
Output 102 Output words 6 bytes
Bit 15 14 13 12 11 10 09 08 07 06 05 04 03 02 01 00
Output
6 bytes
0×00 to 0×05
High Byte–Channel 0 Output Low Byte–Channel 0 Output
High Byte–Channel 1 Output Low Byte–Channel 1 Output
High Byte–Channel 1 Unlatch Alarms Low Byte–Channel 0 Unlatch Alarms
Unlatch Alarm Bits
The unlatching is performed when the unlatch bit is set (1) and the alarm condition no
longer exists. If the alarm condition persists then the unlatch bit has no effect. It is up to
you to keep the unlatch bit set until you get verification from the appropriate channel
status word that the alarm status bit has cleared (0). It is then up to you to reset (0) the
unlatch bit. The module will not latch an alarm condition if a transition from no alarm
condition to alarm condition occurs, and the unlatch bit is set (1).
Word/Bit 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
Channel Alarm Unlatch 0 0 0 0 0 UOC1 UH1 UL1 0 0 0 0 0 UOC0 UH0 UL0
Bit 0: UL0 Unlatch Low Clamp Alarm Channel 0
Bit 1: UH0 Unlatch High Clamp Alarm Channel 0
Bit 2: UOC0 Unlatch Open Circuit Alarm Channel 0
Bits 3~7: Reserved. Set to 0
Bit 8: UL1 Unlatch Low Clamp Alarm Channel 1
Bit 9: UH1 Unlatch High Clamp Alarm Channel 1
Bit 10: UOC1 Unlatch Open Circuit Alarm Channel 1
Bits 11~153~7: Reserved. Set to 0