# Number of days to generate, default = 365
$NumDays 		= 365
$AccessGroup 	= "Gasten"
$ExpiryTime 	= "20:00"
$StartTime 		= "07:00"
$OutputCSV		= "C:\TEMP\wireless.csv"

$SshHost 		= "127.0.0.1"
$SshUser		= "someuser"

$access_codes = @()

# Start SSH session
New-SshSession $SshUser $SshHost
Invoke-Ssh "z"
Invoke-Ssh "conf t"
Invoke-Ssh "wireless F"
Invoke-Ssh "conf t"
Invoke-Ssh "radius-server local"

$i = 0;
do {
	# WSEM format: mm/dd/yyyy hh:mm
	$date = (Get-Date).AddDays($i)
	$date2 = Get-Date $date -Format "dd-MM-yyyy"
	$date = Get-Date $date -format "MM:dd:yyyy"
	$pass = RandomPassword 4
	$user = RandomPassword 4
	$output = "rad-user $user password 0 $pass group $AccessGroup guest expiry-time $ExpiryTime expiry-date $date start-time $StartTime start-date $date"

	# add user through SSH
	Invoke-ssh $output

	$Response = New-Object PSObject
	Add-Member -InputObject $Response -MemberType NoteProperty -Name "Datum" -Value $date2
	Add-Member -InputObject $Response -MemberType NoteProperty -Name "Gebruikersnaam" -Value $user
	Add-Member -InputObject $Response -MemberType NoteProperty -Name "Wachtwoord" -Value $pass
	$access_codes += $Response

	$i++;
} while ( $i -le $NumDays )

# Save and disconnect SSH
Invoke-ssh "write mem"
Remove-SshSession

# Export to CSV
$access_codes | Export-Csv $OutputCSV

# Helper functions
function RandomPassword ([int]$intPasswordLength)
{
   $strNumbers = "1234567890"
   $strCapitalLetters = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
   $strLowerLetters = "abcdefghijklmnopqrstuvwxyz"
   $rand = new-object random

   for ($a=1; $a -le $intPasswordLength; $a++)
      {
         if ($a -gt 3)
           {
      	      $b = $rand.next(0,3) + $a
      	      $b = $b % 3 + 1
      	   } else { $b = $a }
      	 switch ($b)
      	   {
      	      "1" {$b = "$strNumbers"}
      	      "2" {$b = "$strCapitalLetters"}
      	      "3" {$b = "$strLowerLetters"}
      	   }
         $charset = $($b)
         $number = $rand.next(0,$charset.Length)
         $RandomPassword += $charset[$number]
      }
   return $RandomPassword
}

Special thanks to Joel Bennett’s SharpSSH wrapper for PowerShell (located here: http://huddledmasses.org/scriptable-ssh-from-powershell/) which I used to automate the command line commands for the HP WSEM.
This shows the great power of PowerShell for automating virtually anything!