Type 1 Arresters. Use in installations with short-circuit currents up to 100 ka rms DEHN + SÖHNE / protected by ISO 16016

Transcription

1 Type 1 Arresters Use in installations with short-circuit currents up to 100 ka rms

2 Definition of follow current, follow current extinguishing capability and short-circuit withstand capability Follow current I f Current supplied by the electrical power system and flowing through the SPD after a discharge current impulse. Follow current extinguishing capability I fi Prospective short-circuit current that an SPD is able to interrupt without operation of a disconnector. Short-circuit withstand capability Maximum prospective short-circuit current that an SPD is able to withstand / 8172_E_1

3 Type 1 arresters: Tests with a prospective short-circuit current of 100 ka rms carried out at the IPH in Berlin DEHNventil modular DEHNbloc modular DEHNbloc Maxi S DEHNvenCI DEHNbloc Maxi DEHNbloc Maxi NH / 8172_E_2

4 Extended tests at 100 ka rms carried out by the VDE / 8172_E_3

5 Test contents based on EN IEC Test contents: Measurement of the residual voltage / front-of-wave sparkover voltage (section 7.5.2, 7.5.3) Preconditioning with hybrid impulses of 10 kv / 5 ka (3 x 5 impulses on 3 samples each) and a mains-operated voltage source with a prospective peak current I p = 100 ka rms / 220 ka Repeated measurement of the residual voltage / front-of-wave sparkover voltage (section 7.5.2, 7.5.3) to prove full functionality / 8172_E_4

6 Schematic circuit diagram Test series 1: 255 V Test series 2: 440 V Voltages +0 % -5 % i s = 5 kv (1.2/50) MOV 275 V respectively 440 V I pros = 100 ka rms backup fuse NH 500 A, 315 A, 250 A gl/gg impulse current generator 8/20 optical fibre cable SPD V 50 Hz low-voltage supply A control unit A oscilloscope / 8172_E_5

7 Test set-up / 8172_E_6

8 Short-circuit current setting Mains-operated voltage source Short-circuit current I p = 100 ka rms / 220 ka / 8172_E_7

9 Test results Ignition of the type 1 arrester by means of a 10 kv/5 ka hybrid impulse on a mains-operated voltage source with I p = 100 ka rms /220 ka peak Safe handling of discharge processes (15 per sample on 3 samples each) Limitation of let-through integral ( I²t) to extremely small values (the I²t value of the NH fuse certainly exceeds this value) The following fuses and fuses with higher nominal currents do not trip in case of short-circuit currents up to 100 ka rms : DEHNventil / DEHNvenCI 35 A gg DEHNbloc M / Maxi 50 A gg DEHNbloc Maxi A gg DEHNbloc H 63 A gg / 8172_E_8

10 Test results No or only small (depending on the phase angle) mains follow currents occurred In cases where mains follow currents occurred, these were limited to such an extent that even small backup fuses did not trip U[V] I[kA] L1_15: U_tot L1_15: I_follow ms / 8172_E_9

11 Extended product datasheets Due to these extended technical properties, the datasheets of the relevant type 1 arresters were extended: Example DEHNventil modular: Extended technical data for use in switchgear installations with prospective short-circuit currents of more than 50 ka rms (tested by VDE): Maximum prospective short-circuit current: 100 ka rms (220 ka peak ) Limitation/extinction of mains follow currents: up to 100 ka rms (220 ka peak ) Note: The previously reduced backup fuse ratings in case of shortcircuit currents of more than 50 ka rms are not specified any more, because they are no longer required due to the positive test results / 8172_E_10

12 Test results Test reports are available for: DEHNventil modular DEHNvenCI DEHNbloc Maxi S DEHNbloc modular DEHNbloc Maxi DEHNbloc Maxi NH00 DEHNbloc H modular Entwurf BL, / 8172_E_11

13 VDE test reports DEHNventil modular / 8172_E_12

14 VDE test reports DEHNvenCI / 8172_E_13

15 VDE test reports DEHNbloc Maxi S / 8172_E_14

16 VDE test reports DEHNbloc modular / 8172_E_15

17 VDE test reports DEHNbloc Maxi / 8172_E_16

18 VDE test reports DEHNbloc Maxi NH / 8172_E_17

19 VDE test reports DEHNbloc H modular / 8172_E_18

20 Benefits resulting from the high follow current extinguishing capability No restrictions for industrial switchgear installations that require a high short-circuit withstand capability (> 50 ka rms ) Easier installation since the fuse rating does not have to be reduced (e.g. from 315 A to 200 A) in case of short-circuit currents > 50 ka rms Increased safety for small-sized installations due to a considerably higher power reserve of the arresters / 8172_E_19

21 Test results Conclusion: The relevant devices can also be used in switchgear installations with a prospective shortcircuit current of up to 100 ka rms According to the VDE test, the spark gaps extinguish/limit possible mains follow currents without restriction / 8172_E_20