Ziegler–Nichols method

                    Ziegler–Nichols method

The Ziegler–Nichols tuning method is a heuristic method of tuning a PID controller. 

It was developed by John G. Ziegler and Nathaniel B. Nichols. It is performed by

 setting the I (integral) and D (derivative) gains to zero. The "P" (proportional) gain,

 Kp is then increased (from zero) until it reaches the ultimate gain Ku , at which the

 output of the control loop oscillates with a constant amplitude. Ku and the oscillation

 period Tu are used to set the P, I, and D gains depending on the type of controller used:

•  Z–N tuning creates a "quarter wave decay". This is an acceptable result for some

 purposes, but not optimal for all applications.

"The Ziegler-Nichols tuning rule is meant to give PID loops best disturbance rejection 

•  Z–N yields an aggressive gain and overshoot – some applications wish to instead

 minimize or eliminate overshoot, and for these Z–N is inappropriate.

Example :-Tuning a PI controller with the Ziegler-Nichols’ 

closed loop method

I have tried the Ziegler-Nichols’ closed loop method on a level control

system for a wood-chip tank with feed screw and conveyor belt which runs

with constant speed, see Figure 3. The purpose of the control system is

to keep the chip level of the tank equal to the actual, measured level.

The level control system works as follows: The controller tries to keep the

measured level equal to the level setpoint by adjusting the rotational speed

of the feed screw as a function of the control error (which is the difference

between the level setpoint and the measured level).

Figure 4 shows the signals after a step in the setpoint from 9 m to 9.5 m

with a ultimate gain of Kpu = 3.0. The ultimate period is approximately

Pu = 1100 s. From Table 1 we get the following PI parameters:

Kp = 0.45 * 3.0    = 1.35                                                                                         (5)

Ti =1100 s/1.2     = 917 s                                                                                        (6)

Td = 0 s                                                                                                                (7)

Figure 5 shows signals of the control system with the above PID parameter

values. The control system has satisfactory stability. The amplitude ratio

in the damped oscillations is less than 1/4, that is, which means that the

stability is a little better than prescribed by Ziegler and Nichols’.

FCI Previous year Question Papers

FCI Previous year Question Papers for FCI Assistant                      Grade-III (Technical)EXAM

This Question paper contains set of 50 objective type Question Papers that will help students in Cracking the exam.FCI SAMPLE PAPER for Agriculture

FCI AGRICULTURE Solved objective Question:

1. How many factors are identified
for influencing plant growth till
now ?
(A) 55
(B) 60
(C) 52
(D) 50
Answer:C
2, How does the moisture stress
affect the cell
(A) Affect cell division
(B) Affect cell expansion
(C) Cell mortality rate is affected
(D) No effect on cell
Answer:A
3. At the vegetative growth stage,
flowering is stopped in foodgrain
crops, known as-
(A) sigmoid growth curve
(B) determinate growth
(C) indeterminate growth
(D) grand growth period
Answer:B
4. Which one of the following can
be assessed by using the following
equation ?
A= Economic Production / Biomass Production
(A) Panicle emergence rate
(B) Rate of flowering
(C) Harvest Index
(D) Leaf production rate
Answer:C
5. How much radiation energy
percentage radiating on plant is
used in photosynthesis ?
(A) 0-50%-210%
(B) 0-42%-1•66%
(C) 0-25%-0-30%
(D) 0-16%-0-24%
Answer:B
6. The crop with yarns of sunnhemp is prepared in-
(A) 12-15 weeks
(B) 15-17 weeks
(C) 10-12 weeks
(D) 8-10 weeks
Answer:A
7. Which is not an inorganic matter
in the following ?
(A) Magnesium
(B) Iron
(C) Fat
(D) Iodine
Answer:C
8. Which is the highest digestible
protein non-leguminous crop
among the following
(A) Napier
(B) Maize silage
(C) Maize
(D) Iowar
Answer:D
9. Which disease occurs, when
more sorghum is consumed ?
(A) Rickets
(B) Scurvy
(C) Nightblindness
(D) Pellagra
Answer:D
10. Which Sorghum variety is not
multicut ?
(A) Pusa Chari-2
(B) M.P. Chari-2
(C) M.P. Chari
(D) U.P. Chari-1
Answer:D
11. Which is not true in relation to
Bajra ? ‘
(A) Penniseturn typhoides
(B) Graminae family
(C) Chromosome No. – 20
(D) OriginAfrica
Answer:D
12. Which variety of Barley is huskless
(A) Pragati (K 508)
(B) Ritambhara (K 551)
(C) Geetamjali (K 1149)
(D) Karan-3
Answer:D
13. Which is not true in relation to
Gram ?
(A) Subfamily——Papilionaceae
(B) Chromosome No.—22
(C) Acid——Ma.lic and Oxalic
(D) Origin—North America
Answer:D
14. Which does not match in relation
to Cotton ?
(A) C-520 —— Diploid
(B) G-27 — Diploid
(C) Vikas — American
(D) Ranivan — American
Answer:D
15. Which is not matched in relation
to sugarcane ?
(A) Seed treatment—-Aglol 3%
(B) For seed—6-7 month old crop
(C) Sowing—Upper portion is more used
(D) After flowering—Used for sowing
Answer:D
16. Which is not basic principle of
Agronomy ?
(A) To select appropriate materials
for seed & sowing
(B) Management of soil and
climate
(C) Appropriate intercropping
activities management for crop
(D) Livestock management for
Agriculture
Answer:D
17. Where and when was World
Meteorological Organization
established ?
(A) New York – 1980
(B) Washington-1978
(C) Geneva—1978
(D) Rome- 1976
Answer:C
18. Effective cause of atmospheric
pressure is not-
(A) temperature
(B) altitude from the sea level
(C) rotation of earth
(D) soil erosion
Answer:D
19. Which is not correct in the
following ?
(A) X-rays and Gamma rays
— 9% of energy
(B) Visible lighting rays -41%
of energy
(C) Infrared rays -50% of
Y energy
(D) Ultraviolet rays- 10% of
energy
Answer:A
20. Match List-I with List•II and
select the correct answer using
the codes given below-
List-I
(a) Paddy (b) Wheat
(c) Maize (d) Groundnut
List-II ’
1. 20°C 2. 22°C
3. 25°C 4. 26°C
Codes
(a) (b) (c) (d)
(A) 4 2 3 1
(B) 2 1 4 3
(C) 3 4 2 1
(D) 1 3 4 2
Answer:B
21, Which states are the highest 8:
lowest producers of Potato crop ?
(A) Uttar Pradesh and Jharkhand
(B) Gujarat and Assam
(C) Uttar Pradesh & Himachalpradesh
(D) Bihar & Kashmir
Answer:A
22. Which elements are useful in
energy storage, transfer and
bonding ?
(A) N P K
(B) N S P
(C) N K S
(D) None of these
Answer:C
23. Which of the following elements
play an important role in nitrogen
metabolism ?
(A) Magnesium
(B) Manganese
(C) Molybdenum
(D) Iron
Answer:C
24. How much Brinjal seed may be
obtained from one hectare area 7
(A) 150-200 kg
(B) 100-150 kg
(C) 200-300 kg
(D) 75-125 kg
Answer:D
25. Which species of honeybee is not
Indian ?
(A) Apis florea
(B) Apis dorsata
(C) Apis cerana
(D) Apis mellifera
Answer:D
26. Which of the following is the
cross of Karan Swiss ?
(A) Sahiwal x Brown Swiss
(B) Sahiwal x Holstein
(C) Hariyana x Brovsm Swiss
(D) Hariyana >< ]ersey
Answer:A
27. For how many years is Sheep
able to breed ?
(A) 10 years
(B) 7years
(C) 5 years
(D) 12 years
Answer:A
28, l-low much area mz is required
for a Goat ?
(A) 0-9 ~ 1•O m2
(B) 1-1-5 m2
(C) 0-75 — 090 mz
(D) 1-5 – 1-75 mz
Answer:C
29. Goal of extension education is-
(A) To promote income of the
farmers
(B) To promote production of
the crops
(C) To promote new crops
(D) To promote scientific outlook
Answer:D
30. The major fungi that effect foodgrains
in storage are-—
(A) Mucor
(B) Rhizopus
(C) Candida
(D) Aspergillus
Answer:A
31. The leaching loss of Nitrogen (N)
is more in the form of–
(A) Ammonia
(B) Nitrate
(C) Nitrogen
(D) Water solution
Answer:B
32. Which is not a natural factor
affecting soil fertility ?
(A) Topography
(B) Soil age
(C) Air
(D) Parent material
Answer:C
33. Approximately how much area
in lakh hectares of saline and
alkali soils are there in Uttar
Pradesh ?
(A) 15-00 lakh hectares
(B) 12-4 lakhhectares
(C) 10-4 lakh hectares
(D) 14-4 lakh hectares
Answer:B
34. How much percentage of soluble
salts are present in Alkali soils ?
(A) 1% • 2%
(B) 0-1% — 0-2%
(C) 1-5% — 2-5%
(D) 2% ~ 3%
Answer:B
35, How much is the cropped area in
Uttar Pradesh ?
(A) 9%
(B) 11%
(C) 12%
(D) 8%
Answer:C
36. The monsoon airs in the country
reaches at which bank first of
all ?
(A) Coastal region of Orissa
(B) Bay of Bengal region
(C) Coastal region of Kerala of
South Indian region
(D) Kachchh region of Gujarat
Answer:C
37. A.D.P. to A.T.P. change is called
(A) Photosymthesis
(B) Phosphorylation
(C) Transpiration
(D) Oxidation
Answer:B
38. What is the order of C 4 plants 7
(A) Sugarcane — Maize — Sudan
grass — Bajra
(B) Sugarcane — Cotton – Paddy
- Maize
(C) Sudan grass – Sugarcane -
Paddy •- Bajra
(D) Cotton — Maize ~ Bajra —
Sugarcane
Answer:A
39. At what stage are more nutrients
essentially required in cereal
crops ?
(A) Growth stage of plants
(B)` Formation of leaves
(C) Particle initiation
(D) Maturity of crops
Answer:A
40. At which stage of crop, there is
no compehtion for light, moisture
and nutrients 7
(A) Node formation stage
(B) Seedling stage
(C) Grain formation stage
(D) Before maturity stage
Answer:D
41. Approximately how much HCN
dose is harmful for animal feeding
(A) 0-25 gm
(B) 050 gm
(C) 2•50 gm
(D) 3-50 gm
Answer:B
42. Due to which reason is the
Napier Grass mixed with Cluster
bean or Cowpea for feeding ?
(A) Due to high crude fibre
(B) Due to oxalic acid
(C) Due to more carbohydrates
(D) Due to more HCN content
Answer:A
43. Which is the perennial variety of
Elephant Grass (Napier Grass) ?
(A) Pusa Giant
(B) NB-21 `
(C) Pusa Giant Napier
(D) Napier-1
Answer:C
44. More than how much percentage
of loss of urea should not be
during silage fermentation ?
(A) 20% — 22%
(B) 15% — 18%
(C) 10% — 12%
(D) 8% — 10%
Answer:D
45. From where is Krishak Bharati
magazine published ?
(A) G. B. Pant University of
Agriculture & Technology, Pant
Nagar
(B) C. S. A, University of Agriculture & Technology, Kanpur
(C) Narendra Dev University of
Agriculture and Technology,
Fajzabad
(D) Sardar Vallabh Bhai Patel
University of Agriculture and
Technology, Meerut
Answer:B
46. How much minimum temperature is essential for wheat germination
and optimum temperature for crop growth in degree
Celsius ?
(A) 3•5°C-5•5°C and 20°C—22°C
(B) 5•6°C—7•5°C and 16°C—18°C
(C) 8°C—10°C and 30°C—35°C
(D) 10°C—12″C and 25°C—30°C
Answer:D
47. In case of availability of two
irrigations for wheat, at which
critical stage crop should be
irrigated ?
(A) Tillering and Flowering
(B) Crown Root Initiation and
Milking stage p
(C) Crown Root Initiation and
Flowering
(D) Late joint and Dough stage
Answer:C
48. Which is not the symptom of
Khuim disease
(A) Dark grey colour spots on
leaves
(B) Adverse effect on root
growth
(C) More diseases stop the crop
growth
(D) Stem of plants tum and fall 1
down
Answer:A
49. What is the suitable Rabi maize
variety ?
(A) Sharadmani
(B) Azad Uttam
(C) Naveen
(D) Ganga — 5
Answer:A
50. Which disease is not related to
Bajra ?
(A) Green Ear
(B) Ergot
(C) Wilt
(D) Rust
Answer:C