With IPHost Network Monitor you can run simple snmp requests against a Cisco device in your network.
cefcFRUTotalSystemCurrent
Cisco Entity Field Replaceable Unit Control FRU Total System Current
1.3.6.1.4.1.9.9.117.1.1.4.1.1
Total current that could be supplied by the FRU (positive values) for system operations.
Back to CISCO-ENTITY-FRU-CONTROL-MIB MIB page.
IPHost Network monitor allows you to monitor cefcFRUTotalSystemCurrent on Cisco device via the SNMP protocol. Download IPHost Network Monitor (500 monitors for 30 days, 50 monitors free forever) to start monitoring Cisco firewalls right now.