Yes it is normal, if you specify power-supply 1, you get the information only for the power supply.
If you run show environment status you get more detail:
Cat6kIOS#show environment status
backplane:
operating clock count: 2
operating VTT count: 3
fan-tray:
fantray fan operation sensor: OK
VTT 1:
VTT 1 OK: OK
VTT 1 outlet temperature: 32C
VTT 2:
VTT 2 OK: OK
VTT 2 outlet temperature: 34C
VTT 3:
VTT 3 OK: OK
VTT 3 outlet temperature: 36C
clock 1:
clock 1 OK: OK, clock 1 clock-inuse: in-use
clock 2:
clock 2 OK: OK, clock 2 clock-inuse: not-in-use
power-supply 1:
power-supply 1 fan-fail: OK
power-supply 1 power-output-fail: OK
module 1:
module 1 power-output-fail: OK
module 1 outlet temperature: 30C
module 1 device-2 temperature: 35C
RP 1 outlet temperature: 36C
RP 1 inlet temperature: 37C
EARL 1 outlet temperature: 29C
EARL 1 inlet temperature: 30C
As per:
http://www.cisco.com/en/US/products/hw/switches/ps700/products_tech_note09186a008015bfa8.shtml
