Not possible from a CLI on 4006 switches. If you have a IOS based 4500 switch, you can use sh idprom power-supply 1 and sh idprom power-supply 2
Switch#sh idprom power-supply 1
Power Supply 1 Idprom :
Common Block Signature = 0xABAB
Common Block Version = 1
Common Block Length = 144
Common Block Checksum = 4723
Idprom Size = 256
Block Count = 2
FRU Major Type = 0x4501
FRU Minor Type = 2
OEM String = Cisco Systems, Inc.
Product Number = PWR-C4K-2800AC
Serial Number = SONXXXXXXXX <<<<<<<<<<<---------
Part Number = 34-1978-01
Part Revision = P2D
Manufacturing Deviation String =
Hardware Revision = 1.0
Manufacturing Bits = 0x0000
Engineering Bits = 0x0000
Snmp OID = 0.0.0.0.0.0.0.0
Power Consumption = 2800
RMA Failure Code = 0 0 0 0
Power Supply Block Signature = 0x4501
PowerSupply Block Version = 1
PowerSupply Block Length = 20
PowerSupply Block Checksum = 108
Feature Bits = 0x0000000000000000
Current @ 110V = 0
Current @ 220V = 17
StackMIB OID = 0