PR Number | Quantity | Items Required | Posting Date | Closing Date | Closing Time |
10256053 | 1 | METERING UNIT 200/100/5A 33 KV 110V | 05/10/2023 | 10/10/2023 | 10:00 |
33KV METERING UNIT SPECIFICATION
- CHARACTERISTIC OF THE ENVIRONMENT
The Metering Unit shall be capable of proper functioning under the following environment
-
- Average altitude of 1500m above sea level
- Ambient temperature 0 degree to 38 degree centigrade and meter housing or enclosure temperatures could be as high as 45 degrees centigrade.
- Humidity 13gm/m3 absolute and 95% relative before storms with vapour pressure 17mmHg.
- Equipment will operate within the tropics and is subject to sudden ambient air temperature changes of the order of 10 degrees centigrade occurring at the onset of the rain season but the barometric pressure at any given place does not vary by more than 10mm Mercury. Frequent and severe lighting storms occur during summer months, with isokeraunic levels varying between 40 and 110 thunderstorm days per annum.
- Particular attention should be paid in the design of all equipment to ensure that there is no damage to working parts or insulation through the ingress of dust, insects, vermin which are prevalent for long periods in the year
- GENERAL CHARACTERISTICS
- Applicable Standards.
The Metering Unit shall conform to BS 3958, BS 3938, BS 3941 (1973) and IEC 185, IEC186, IEC61869-1, IEC 61869-2, IEC 61869-3, IEC 61869-4 as appropriate.
- Immunity to Electrostatic Discharges
As per IEC 801-4
- Immunity of Electromagnetic Transients
As per IEC 801-3
- Emitted Radio Frequency Interference
Must conform to CISR 14
- Operating temperature range
Must conform to IP54 degree of protection
Temperature Range Normal: 0 to 55 degree centigrade
Short Duration: 0 to 60 degrees centigrade
- Humidity
Up to 95% non-condensing
- Shock Withstand
As per IEC 68-2-27
- Vibration Withstand
As per IEC 68-2-6
3. GENERAL TECHNICAL REQUIREMENTS
Particulars of Electrical System
- Outdoor, earthed, 3 phase, overhead construction.
- Operated at 50Hz variable between plus or minus 2 ½%
- A highest system voltage not exceeding the normal by more than 10%
- Earthed so that the earth fault factor will be less than 1.5 at any location.
- Calibration and Acceptance Testing of Metering Units & Voltage Transformers
- In addition to the manufacturer’s Test Certificates, the Metering Unit shall also be brought to our testing facilities at either Harare or Bulawayo Meter Test for verification.
5. PARTICULAR TECHNICAL REQUIREMENTS
- The metering unit shall comply with BS 3958, BS 3938 and IEC 185, IEC 61869-1, 61869-2, 61869-3, and 61869-4 unless otherwise specified.
- The combined instrument transformers (metering unit) shall be of the outdoor type and shall be designed for metering of three phase loads using the two wattmeter principle (3 phase 3 wire metering configuration).
- The 33kV Metering Unit shall have CTs of current ratios of 300/200/100/5Amps
- The Metering Unit shall have VTs with a voltage ratio of 33 000/110V
- The metering unit shall be of the outdoor oil filled type.
- The Basic Insulation Level shall be 200kV.
- The AC one (1) minute Test Withstand Voltage shall be 70kV.
- The Short Time Withstand Current (3 seconds) shall be 13kA
- The Metering Unit shall comply with the following performance
- Nominal Voltage Ratio: 33 000/110V
- Current Ratio (33kV): 300/200/5A
- Burden : 10 VA for CTs and 50VA for VTs
- Accuracy class (Both CTs & VTs): 2 or better
- Basic Insulation Level : 200kV
- Frequency: 50Hz
- Thermal Current: 2 times the rated current of CT
- Limits of Ratio Error: As per accuracy class requirements
- Limits of Displacement error: As per accuracy class requirements
- The Metering Unit shall be provided with suitable lifting arrangement to lift the entire unit. Lifting arrangement (Lifting eye) shall be positioned in such a way so as to avoid any damage to the porcelain housing or the tanks during lifting for installation purposes.
- The metering units shall have arcing horns fitted.
6 NAMEPLATE
The Metering Unit shall carry a non-corrosive, legible name plate marking with the following details:
- Manufacturer’s Name Identity
- Serial Number of Unit
- Rated CT primary and secondary currents
- Rated VT primary and secondary voltage
- The Rated Frequency e.g. 50Hz
- The Rated Highest System Voltage
- Power Frequency Withstand Voltage
- Impulse Withstand Voltage
- The Rated short time current in kA and the rated Time expressed e.g. 13kA/3s
QUOTATION SHOULD BE IN US$ PAYABLE AT THE PREVAILING INTERBANK RATE AND MUST BE CLEARLY STATED.
DOCUMENTS REQUIRED
Companies must submit together with quotations:
- Proof of Tax Clearance Certificate ITF 263.
- Proof of VAT Certificate / Declaration of VAT registration Status
- Proof of Registration with PRAZ in the relevant category.
- State payment terms.
- State Quotation Validity Period.
- State delivery period.
ZETDC STANDARD PAYMENT PERIOD IS 30 DAYS
QUOTATION SHOULD BE VALID FOR A PERIOD OF 30 DAYS AND MUST BE CLEARLY STATED
DELIVERY PERIOD SHOULD BE AT MOST 10 DAYS AND MUST BE CLEARLY STATED
SUBMISSION OF QUOTATION
All quotations must be enclosed in sealed envelopes, endorsed on the outside with the advertised RFQ number, the closing date and Time and deposited in the Tender Box, Electricity House, Wynne Street. Harare Zimbabwe before 10:00Hrs on the closing date notified.
Email and faxed quotation will not be considered.