<?xml version="1.0" standalone="yes"?>
<?xml-stylesheet type="text/xsl" href="..\..\XSLTemplates\NVSStyleSheet.xsl"?>
<Parameter>
<ParameterFamily>drum</ParameterFamily>
<LongName>
drive_friction
</LongName>
<Name>
dfrict
</Name>
<AppliesTo>
<UnnumberedList>
<ListItem><TextApplies>All</TextApplies></ListItem>
</UnnumberedList>
</AppliesTo>
<Description>
<DescriptionText><text>
Nominal starting friction for a given drum servo system.  This parameter is
used during drum calibtration.  If a drum calibration is successful, this
value is subtracted from the drive value required to move the drum from a
stopped condition.   The resulting value will become the drum nvs parameter
"doff".
</text></DescriptionText>
</Description>
<Type>
integer
</Type>
<Default>
<UnnumberedList>
<li>33 (VLF)</li>
</UnnumberedList>
</Default>
<Default>
<UnnumberedList>
<li>15 (3244)</li>
</UnnumberedList>
</Default>
<Default>
<UnnumberedList>
<li>0 (Trendsetter NEWS)</li>
</UnnumberedList>
</Default>
<Range>
<UnnumberedList>
<li>0 to 50</li>
</UnnumberedList>
</Range>
<ArraySize>
</ArraySize>
<Notes>
<DescriptionText><text>
Procedure for setting dfrict.
</text></DescriptionText>
<DescriptionText><UnnumberedList>
<ListItem><Text>WARNING: high voltages may be present.</Text></ListItem>
</UnnumberedList></DescriptionText>
<DescriptionText><NumberedList>
<ListItem><Text>Connect a volt meter between any two phase outputs from the drive amp J4 (eg pin 2 - pin 3).</Text></ListItem>
<ListItem><Text>enter "Drum idle"</Text></ListItem>
<ListItem><Text>enter "set drum doff 0"</Text></ListItem>
<ListItem><Text>enter "drum torque 0"</Text></ListItem>
<ListItem><Text>The Voltage should be below 4V,</Text></ListItem>
<ListItem><Text>if not enter "drum torque 4" if the voltage goes up then the drum amp deadband too</Text></ListItem>
narrow (or negitive) to perform this procedure and should be replaced or calibrated anyway.
<ListItem><Text>enter "drum torque &lt;x&gt;"  repeatedly where x is increased by one at a time, until the voltage</Text></ListItem>
increases by &gt;30% (typically &gt;10V). (No more than torque 40 should be required)
Note: The voltages that you read are dependent on the drum position, if you susspect that
the voltage is higher than you expect then rotate the drum a bit by hand.
<ListItem><Text>This value of torque is the true dead band.</Text></ListItem>
<ListItem><Text>enter "set drum doff 0"  and "set drum dfrict 8" for 3244 and  "set drum dfrict 8" for VLF</Text></ListItem>
This is an impirically determined deadband that the PID likes to see, it seems to prefer
some deadband over a perfectly calibrated system.
<ListItem><Text>Enter "drum cal"</Text></ListItem>
<ListItem><Text>Enter "set drum doff" to read the new value of doff, then set dfrict to</Text></ListItem>
(doff  minus  true_dead_band) using "set drum dfrict &lt;#&gt;"
<ListItem><Text>enter "set drum doff 0" and  "drum cal"</Text></ListItem>
<ListItem><Text>save settings using "nvs save drum"</Text></ListItem>
</NumberedList></DescriptionText>
<DescriptionText><text>
For non-VLF Trendsetters with new 10A drum drive, this value should be set to 0.
These machines will have the "sys hdp (high_pwr_drives_inst)" parameter set to 1.
</text></DescriptionText>
</Notes>
<Partition>
cfg
</Partition>
<SeeAlso>
<UnnumberedList>
<li><Link><LinkAddress>../commands/drum_cal.xml</LinkAddress><LinkTitle>Command: drum cal</LinkTitle></Link></li>
<li><Link><LinkAddress>../nvs/drum_cfg_doff.xml</LinkAddress><LinkTitle>NVS: drum doff</LinkTitle></Link></li>
<li><Link><LinkAddress>../nvs/sys_cfg_hpd.xml</LinkAddress><LinkTitle>NVS: sys hpd</LinkTitle></Link></li>
</UnnumberedList>
</SeeAlso>
<OtherLinks>
<li><Link><LinkAddress>..\..\ShowAllErrors.htm</LinkAddress><LinkTitle>Firmware 0 Error Index</LinkTitle></Link></li>
<li><Link><LinkAddress>..\..\ShowAllCommands.htm</LinkAddress><LinkTitle>Firmware 0 Command Index</LinkTitle></Link></li>
<li><Link><LinkAddress>..\..\ShowAllNVS.htm</LinkAddress><LinkTitle>Firmware 0 NVS Index</LinkTitle></Link></li>
</OtherLinks>
<Updated>
Updated: Wed Jul 16 19:36:47 2008 PST
</Updated>
<Links>
</Links>
</Parameter>
