There is no difference between HMI and MMI.
MMI stands for Man Machine interface.
HMI stands for Human Machine Interface.
Then there will rise a question why there are two terms.
In the ewarlier days only men used to work in any control
room. But now a days womwn are also working in all Controll
rooms.Hence the word HMI has been ome in usage.Just to
avoid any doubt that in control both men and women can work.
Answer no 5 seems to be correct with answer no 3. Intially
the machine interfaces are having limited capabilities and
then enhanced to higher levels. So answwer no 3 may be
taken as correct and while renaming while tech advancing
Answer no 5 must have been considered.
There was an another term calleed GUS: Global User Staion
But HMI stands dominating. MMI (favour towards men), GUs
(not specific for machine interface)
I am going to attend a recruitment drive by Schneider in 2
weeks. They have a technical test in the beginning. I would
like to know what are the areas i should concentrate on
while preparing for the test. My major is Electronics and
1. How many output signals do wew have in process control?
2. Could you write down the names of the pre-commissioning
and commissioning stage test instruments and explain them
(more than 5 items)?
3. What is the first step to commission a transmitter on
4. What is RTD?
5. Find the output value in MA of a temperature transmitter
(RTD Type) at 120degree celius?
6. What is the O/P signal of a pneumatic transmitter?
7. What is the O/P signal of an elctronic transmitter?
8. What is the close loop and open loon?
If a control valve is hunting means means if we are giving
50% to the cv, the cv will open at 51% then slowly slwoly
it will reaches 49% , then it will reaches again 50%, this
type of action occured frequntly.. so what to do for solve
this problem. The possible cause is in volume booster or
positioner's relay.. positioner is double acting .. and
make siemens..sipart.The cv is double acting and mounted
for anti surge operation, it having 4 nos. volume booster,
one sov, one positioner, etc..?