【低壓制櫃設計】低壓制櫃的測試（T&C of LV Switchboard 2 of 2）- 出廠驗收測試（FAT）和現場驗收測試（SAT）（Part 7）

在前一篇，我們介紹了低壓制櫃的FAT和SAT測試中Function Test 功能測試（TP5），以及ATS的Test （TP9）。見鏈接：

【低壓制櫃設計】低壓制櫃的測試（T&C of LV Switchboard 2 of 2）- 出廠驗收測試（FAT）和現場驗收測試（SAT）（Part 6）

今天，我們介紹一下FAT中的Temperature Rise Limits Test（TP10）溫升極限測試。

Temperature Rise Limits Test 溫升極限試驗是用以測試和確定在額定負載下掣櫃和组件的溫升是否超出標準的極限。一般只在FAT中進行。

在測試中，為確保測試的結果不會受到測試場地的環境因素影響，應在測試階段會使用兩支溫度計在掣櫃的一半高度和相距掣櫃1米外的位置量度室内溫度（ambient air temperature）。

進行溫升極限試驗時，掣櫃的總開關、總匯流排、每一個線路和配電匯流排都應接上其額定容量值的负载。所有電路的额定電流總和，如高於總開關或總匯流排的额定载流量；必須将各個電路组成不同的組合，務求總開關、總匯流排和每個電路都能在滿载下進行測試。當然這是最理想的情況，但常常因為時間的限制，降低測試的次數，而可以免去一些支路匯流排的測試，只對總/主匯流排進行溫升測試。

測試項目：Temperature Rise Limits Test 溫升極限測試

測試目的：

                  To check the temperature rise limit when the circuits are loaded 

測試儀器：  

                  (i) 10 kVA single phase variable transformer

                  (ii) 10 kVA single phase current transformer

                  (iii) 5A secondary current transformer

                  (iv) Thermocouples

                  (v) Temperature loggers

測試步驟：

(1) Arrangement of Test Panel

Check that the arrangement of the L.V Switchboard under test is correct and record all necessary information on the approved test form.

(2) Test Connections

Test connections are fitted to each loaded circuits and short circuited at their remote end from the switchboard with the dimension of test conductors.

Test current for the test is provided via 3 current transformers (1 per phase). These current transformers are connected to three individually variable voltage supplies, one per phase, for the provision of adjustment of the injected current independently. The typical connection method is shown in the figure of this section.

(3) Current Measurement

All outgoing circuits are equipped with one CT for each phase. Each of these CT's is then connected to an ammeter for current measurement. This arrangement facilitates regular monitoring of the intake current and distribution of the current to each test circuit.

(4) Temperature Measurement

Temperatures are measured using thermocouples and temperature loggers.

Thermocouples are adhered to the busbar surface by flame retardant tape at points of particular interest, where high temperatures are likely to be experienced. Details of the positions of thermo-couples are marked on the L.V Switchboard layout drawing.

Ambient temperature is measured from the average of two thermo-couples adhered to both sides of the switchboard at least 1 metre apart from each other and approximately 1.2 metres above the ground.

The locations of the thermocouples are shown on the temperature-rise test drawing. （Test points的數量及位置在測試需要經過業主/工程師審批，一般沿著主bar會儘量在不同節點設置Test points）

(5) Duration of Test

Current is applied until temperature rise approaches the steady state, i.e. rising at not more than 1°C per hour, as stipulated by clause 10.10.2.3.1 of BS EN 61439-1:2011. During this period, slight mains voltage variations and increasing impedance of the test piece necessitate an occasional adjustment to the applied voltage. Temperatures are measured at hourly intervals throughout the test.（Temperature loggers會自動記錄並保存溫度數據）

(6) Test Result

The temperatures measured in each hour are recorded on the client-approved test form. The temperature rise shall not exceed the values as stipulated in Table 6 of BS EN 61439-1:2011.

測試報告：（Test report is initialled by FED-SUPREMETECH LIMITED）