Analog milliamp outputs clamped to an invalid value cause SNAP module to go off-line

Applies To:

SNAP-PAC-R1
SNAP-PAC-R2
SNAP-PAC-EB1
SNAP-PAC-EB2
SNAP-PAC-SB1
SNAP-PAC-SB2
SNAP-UP1-ADS
SNAP-UP1-M64
SNAP-UP1-D64
SNAP-B3000-ENET
SNAP-ENET-S64
SNAP-ENET-D64

Versions Affected:

Problem was introduced in version: R6.0a

Symptoms:

A SNAP analog output module assigned an Upper or Lower Clamp value outside its valid output range, is forced offline. The module cycles online and offline until valid clamp values are written. Depending on the application used to view the module's readings, a '-nan' or -32768 may be reported.

Modules affected:

SNAP-AOA-3 SNAP-AOV-5
SNAP-AOA-23 SNAP-AOV-7
SNAP-AOA-23-iSRC SNAP-AOV-25
SNAP-AOA-28

Example 1:

The following settings for a SNAP-AOA-3, 4-20 mA module cause the problem:
Output = 4 mA
Upper Clamp = 5 mA
Lower Clamp = 50 mA← This is out of range

Example 2:

The following settings for a SNAP-AOV-5, 0-10 VDC output module cause the problem:
Output = 0 VDC
Upper Clamp = 0 VDC
Lower Clamp = 25 VDC← This is out of range

Additional symptoms as seen from PAC Manager's Status Read page:

Smart Modules Present mask indicates the module is offline.
Times Discovered for the module increases.
Arcnet Reconfigs Detected does not show count as increasing.

The Upper and Lower Clamp values are entered in PAC Manager using this window: (Tools→Inspect, Point Config)

[image1]

Likewise, the clamping limits may be entered in PAC Control:

[image2]

Resolution:

Opto 22 is investigating this issue.

Questions?

Contact: Opto 22 Product Support.
Phone: 800-835-6786 or 951-695-3080
Email: support@opto22.com

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