L83EX, the external load control mode was enabled in the MKV software and checked out successfully with the L83EX forced to a "1". Next was to add the button to the HMI and enable the external load signal in the CMDSTATE block. I am new to working on CMDSTATE blocks and would appreciate details on configuring the existing block. Preset4 and Perm4 correspond to the L83EX output for external load control.

Originally, there was only load control enabled for Preselect, Base, and Peak. On the MKV processor: In order to enable external load, Preset4 was left as LFALSE and Perm4 was changed to LTRUE. After performing the change on input for Perm4, should the existing "mask" value be changed? On the HMI: An additional button was created for External Load. Somehow, I'm having trouble making the L83EX output change into a "1" using the CMDSTATE block.

 

Command State blocks have "masks" for both the Preset and Enable functions (they are usually four-character values). To make the Preset active or enable the feature, the Masks have to be set properly. It's not enough to just change the values of the Preset or Enable logic; the block has to be configured to "recognize" the Preset and/or the Enable logic inputs for a particular value.

Also, you're probably aware of this but the signal from the HMI has to be an analog value that gets passed to the block from the display, and then the block must be configured to look at the Preset and/or the Enable logic values by the value of the masks.

It's pretty difficult to explain; sorry. Those blocks are about the most difficult things in the Mark V. Have a look at the description in the Mark V Application Manual, GEH-6195, Appendix C, I believe. And then compare what you read with one or two of the other CMDSTATE blocks and it will (eventually) become clearer.

 

Configuring the CMDstate block is one of the more harder tasks of mark v. however this can be done if you have a proper example laid out. i am listing the step by step procedure for the configuration of the external load setpoint.

step 1 : configuration of the enumerated data type and the associated long integer SC43LOAD
The SC43LOAD is the long integer which is passed from the HMI to know which mode is under selection.
the value of SC43LOAD will be 1 for preselect load, 2 for baseload , 3 for peak load and 4 for external load. The push button must be configured to reflect this.

Step 2 :Configuration of the command state block.
<pre>
a. Configuration of the Lout_(state). in the command block already availabe in the application software rung you will have this
LOUT0 - L83CA (CANCEL LOGIC , MACHINE RIVETS BACK TO DROOP)
LOUT1 - L83PS (PRESELECT CONTROL LOGIC)
LOUT2 - L83B (BASE LOAD LOGIC)
LOUT3 - L83P (PEAK LOAD LOGIC)
LOUT4 - L83EX (EXTERNAL LOAD LOGIC , THIS MUST BE CONFIGURED IN THE CMD STATE BLOCK IF NOT AVAILABLE)

b. configuration of the LPRES_n (preset logic) - in the command bock already available you will have the following
LPRES0 - LOAD_CLEAR ( SELECTS THE CANCEL LOGIC)
LPRES1 - LOAD1_PRSET ( MOSTLY USED IN FAST START LOGIC , MAY NOT BE PRESENT)
LPRES2 TO LPRES7 - SET TO FALSE
as you will be using enumurated datatype , you need not change the preset logic, but if you run into trouble configuring the sc43load , then you will have to use preset to configure the external load logic. in that case assign a new signal (eg - LOAD_EXTNL which changes state to 1 when the external pushbutton is pressed )to the LPRES4.

c. Configuration of the PERM_n (permissive logic) - in the above example as we are using LOUT0 to LOUT4 the permissive logic PREM1 to PREM4 must always be set to true. the other can be set to flase.
LPRES0 - TRUE
LPRES1 - TRUE
LPRES2 - TRUE
LPRES3 - TRUE
LPRES4 - TRUE
LPRES5 - FALSE
LPRES6 - FALSE
LPRES7 - FALSE </pre>

 

d. Configuration of the Kmask - the Kmask is a 16 bit binary number which is used by the CMDSTATE TO determine the access logic for the preset and the

permissive logic. in markv the KMASK is input as a HEX number (actually a 4 digit hex converted no representing the 16 bits). The most significant byte is

used for the control of preset logic and the least significant byte is used for the control of the permissive logic. for the above given example the value of

the Kmask will be <pre>
Binary : 00000011 00011111
hex : 03 1F
decimal: 799

Kmask and the logic colleration

----------------------------- msbyte of kmask----------------------------------ls byte of kmask -------------------
LPRES7 LPRES6 LPRES5 LPRES4 LPRES3 LPRES2 LPRES1 LPRES0 : LPREM7 LPREM6 LPREM5 LPREM4 LPREM3 LPREM2 LPREM1 LPREM0 </pre>
so how this is configured depends on the configuration of the LPRES and the LPREM. if a LPRES is used then that respective bit is to be 1. i have uploaded

the figure detailing the configuration of the CMDSTATE block and given an example of the Kmask is to be set.

http://www.2shared.com/photo/nK6AVTMB/command_state.html

hope this helps in clearing all the doubt regarding the CMDSTATE block configuration.

As CSA said it is quite difficult the explain the CMDSTATE logic , but hey picture speaks a thousand words right .

wite in for any more clarifications and details.

 

Hi, The link:
http://www.2shared.com/photo/nK6AVTMB/command_state.html
Seems to be inactive. Could you please reload the link