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equilibrium period. It is recommended that the preconditioning period end with an automatic or manually-induced defrost cycle when testing at application rating conditions for outdoor air stated in Table 3 and Table 9 of EN 14511-2:2004. 4.4.4.3 Equilibrium period The equilibrium period immediately follows the preconditioning period or the defrost cycle and a recovery period of 10 min that ends a preconditioning period. A complete equilibrium period is one hour in duration. Except as specified in 4.4.4.7, the heat pump shall operate while meeting the test tolerances specified in Table 4. 4.4.4.4 Data collection period The data collection period immediately follows the equilibrium period. Data shall be sampled at equal intervals that span every 30 s or less, excepted during defrost cycles as specified below. During defrost cycles, plus the first 10 min following defrost termination, data used in evaluating the integrated heating capacity and the integrated power input of the heat pump shall be sampled more frequently, at equal intervals that span every 10 s or less. When using the indoor air enthalpy method, these more frequently sampled data include the change in indoor-side dry bulb temperature. When using the calorimeter method, these more frequently sampled data include all measurements required to determine the indoor-side capacity. EN 14511-3:2004 (E) 16 For heat pumps that automatically cycle off the indoor fan during a defrost, the contribution of the net heating delivered and/or the change in indoor-side dry bulb temperature shall be assigned the value of zero when the indoor fan is off, if using the indoor air enthalpy method. If using the calorimeter test method, the integration of capacity shall continue while the indoor fan is off. The difference between the leaving and entering temperatures of the heat transfer medium at the indoor heat exchanger shall be measured. For each interval of 5 min during the data collection period, an average temperature difference shall be calculated, DTi (t). The average temperature difference for the first 5 min of the data collection period, DTi (t=0), shall be saved for the purpose of calculating the following percent change: ( ) () ( ) 100 0 0 % ´ ú û ù êë é D = D = - D D = t t t i i i T T T T (8) 4.4.4.5 Test procedure: When a defrost cycle ends the preconditioning period If the quantity %DT exceeds 2,5 % during the first 35 min of the data collection period, the heating capacity test shall be designated a transient test (see 4.4.4.7). Likewise, if the heat pump initiates a defrost cycle during the equilibrium period or during the first 35 min of the data collection period, the heating capacity test shall be designated a transient test. If the above conditions do not occur and the test tolerances specified in Table 2 are satisfied during both the equilibrium period and the first 35 min of the data collection period, then the heat capacity test shall be (责任编辑：admin) |
