Describe the general instructions on the care, proper sealing and testing of Meters along with special instructions to be observed in case of H.T metering cubicles .( Qno 4, P1 Dec 2015)

The following are the general instructions on the care, proper sealing and testing of meters:—
 

(1) SEALS:
All the H.T. meters should be sealed under the supervision of Divisional Engineer/Assistant Divisional Engineer Meters, L.T. and other meters under the supervision of Assistant Divisional Engineer/Assistant Engineer/Meters. The sealing plair of MRT should be distinctly different from that of the field staff. The seals of the meters received from MRT should not be broken by the filed staff.

N.B. (1) The lineman may seal cut outs of all the single phase domestic services. The line inspector may seal cut outs of all the three phase domestic services upto 5 K.W. and all single phase non-domestic
services. The Section Officer may seal cut outs of all other L.T. category services.
(2) Sealing pliers should be in the personal custody of the person to whom they are issued. They should never be lent to anyone else even of higher rank and should be. kept locked when not under use. The
superintending Engineer will issue for each distribution a list of authorised sealers with the type and the form of the seals and a copy of it should be carefully maintained in the distributionoffice. 115
3) In no circumstances should supply be given unless both the meter and the cut-outs are sealed separately as indicated above. 

4) The sealing should be done by keeping the sealing plier perpendicular to the sealing wire. If it is done any other manner there is possibility of slippage of seal.

(2) CUT-OUT : The phase cut-outs should be mounted after the meter on one side of the meter box on the outside. They should be fixed by means of cup headed bolts with lock nuts inside the meter box. The hinges should be revetted with good heads or should be sealed by the Line Inspector or Lineman.

(3) CONNECTIONS. All cables and connections up to the supply side of the meter should be metal clad/P.V.C. pipe throughout, i.e., if the cable itself is not armoured, it should be enclosed in continuous screwed piping. If flanges or running couplings are to be employed, they shouldbe sealed by the Section Officer and the facts recorded.

(4) METERS: The lineman may seal the meter terminal covers of all single phase domestic services after he himself has made the connections and seen that all the connections are tight. The line inspector may seal the meter terminal covers of all 3 phase domestic services upto 5 K.W. and all single phase non-domestic services. The Section Officer may seal the meter terminal covers of all other L.T. categories of services except CT meters. In respect of L.T., CT meters, the meter terminal covers and pilfer proof box must be sealed by the Assistant Divisional Engineer meters. However, the in coming and out going service connection cables from the pilfer proof box may be sealed by the Section Officer. The Assistant Divisional Engineer may release and seal all H.T. services up to 1000 KVA. The Divisional Engineer may release and seal all the H.T. services above 1000 KVA. 

The following special instructions must be observed in the case of H.T. metering cubicles:-
a) Sealing arrangements shall be done for AB switches at consumer premises.
b) Sealing arrangements shall be provided for sealing of the top cover and inspection cover of the metering cubicles and MRT seals shall be provided for the top cover, inspection cover and secondary terminal of the metering cubicles.
c) Multiplying factor used shall be prominently painted on the meter and meter card also
d) Effective insulation is to be provided to the terminals of the metering cubicle.
e) The fuses provided for the P.T. on the L.T. side shall be removed and give direct connection to the meter. 116
f) The metering cubicles shall be connected in the Max C.T. ratio provided so that the multiplying factor should be calculated without ambiguity.
g) Test blocks shall be provided to the meters. The test blocks should be effectively sealed by M.R.T.
h) It should be ensured to have a separate set of C.Ts for protection, recording load etc. instead of combining them with billing meter circuit.

REF : APED Manual Volume I, Page no 114 - 115 , Para No 162, 163

What are the registers maintained in the Stores section of the system in connection with the purchase of stores ? ( Qno 5b in P1 Dec 2015)

The following registers are maintained in the Stores section of the system in connection with the purchase of stores:—
a) Register of purchase orders
b) Register of rate contract
c) Register of indents sent to Chief Engineer
d) Register of T. Notes
e) Register of transport bills
f) Register of Railway receipts and Lorry receipts.
g) Register of rejected materials
h) Register of Check measurements
i) Register of ‘C’ forms
j) Register of Theft of materials
k) Register of Demurrages and wharefages.
1) Register of Test Checks
m) Register of Stores Received Books and Stores Issues Books.
n) Register of Gate passes
o) Register of Requisition and Devolutions.
p) Register of Auction materials .
q) Form no 13 Report on receipt of materials in stores.
r) Register of specimen signatures

REF : APED Manual I, Page No 279, Para No 318

What is BIN CARD ?

Bin Card

A Bin Card (Form--S--13) is hung up outside each bin or rack in the stores. The minimum and maximum quantities to be stocked in respect of the material as fixed by the Superintending Engineer are noted in it. Each time articles are placed into or taken out of a bin or rack an entry is concurrently made in the Bin Card and the balance struck. Where materials are stocked out—door, Bin Cards should be separately maintained by the Section Officers and all issues and receipts concurrently noted. The Bin Cards should show the balances at any moment and this should tally with numerical accounts. An entry of receipt of a material is first made in Stores Received Book and then in the Bin Card while in the case of issue an entry is made first in the Bin Card and then in the Stores Issued Book.

REF : APED Manual Volume I , Page No 284, Para No 324

What are the limitations of Energy Audit ? (Qno 1c, P1 Dec 2015)

LIMITATIONS OF ENERGY AUDIT
 

The losses arrived at can at best indicate only the range of losses but not a very accurate figure on account of the following constraints.
• High cost of metering at EHT & HT points. As meters are to be connected using instrument transformers CT & PT for stepping down the primary parameters to levels acceptable by meters the errors in the CT & PT together with errors in meters add up to inaccuracies. The high multiplying factors cause to magnify even small errors in registration of reading.
• Simultaneous reading of all meters at every metering point is not possible unless an expensive automatic logging is provided.
• Near impossibility of reading meters at all consumers at one time. Each State Electricity Board have about 10 million consumers spread over vast area. Also SEBs have different meter reading cycles such as monthly, bi-monthly, trimonthly etc., by grouping number of services.
• Assessed consumption at services with defective meters to be added up to sales.150
• Assessed consumption of unmetered services such as agriculture, have large bearing on arriving at the T&D losses.

Ref: APED Manual Volume I , Page No 149, Para No 228

Explain Briefly Direct and Indirect Methods of Energy Audit ? ( Qno 1b, P1 Dec 2015 )

DIRECT & INDIRECT METHODS OF ENERGY AUDIT

I) Direct Method: In this method, losses are found on the basis of difference of units sent out and received at the end of each element in the power system. The main advantage is that it is straight forward and simple. The major constraints are that it calls for metering of very high class of accuracy and the difficulty, in simultaneous reading of meters. Due to employing CT & PT of very high ratios the multiplying factors are very large and any small variation will result in large discrepancy.

II) Indirect Method: The losses are determined by simulation of the network. With the advent of powerful mini and micro computers at affordable prices and good models for simulation of T&D networks this is more popular and practical. Even in this system, metering at critical points in the system for operating parameters such as power factor, coincident fact, or load factor, loss factor and hourly load data is required for use in simulation.

Ref : APED Manual Volume I, Page no 149,  Para no 227

What are the objectives of Energy Audit ? ( Qno 1a, P1 Dec 2015 )

OBJECTIVES OF ENERGY AUDIT

1. Identification of areas of High Technical Losses and to take steps to reduce the same
2. Arrive at system improvements necessary
3. Obtain guidance for system planning
4. Identification of areas where commercial losses are very high and to take remedial steps
5. Pinpointing areas where theft of energy by direct tapping is rampant and take
6. steps to plug up the leakages

APED Manual Volume I, Page No 148,  Para 226

Indian Electricity Grid Code

Indian Electricity Grid Code

Indian Electricity Grid Code