Do s and don'ts of connection systems Are there any options when the clearance and creepage distances are not sufficient for UL 1059?

Transcription

1 Do s and don'ts of connection systems Are there any options when the clearance and creepage distances are not sufficient for UL 1059? Speaker: Wolfgang Sichmann, Product Manager PCB Plug-In Connectors, Weidmüller Interface GmbH &Co. KG

2 Contents - Introduction - UL device approvals. Listing - UL component approvals, UL UL 1059 application groups for Terminal Blocks and Connectors - UL 1059 case study of clearance and creepage problem - Option to clear the 600 V barrier via UL 508 / UL840 device approval - For connectors soldered on the printed circuit board - Pollution degree / overvoltage category / clearance and creepage distances - for PCB terminals - Pollution degree / overvoltage category / equivalents of clearance and creepage distances - Wire-end ferrules for the American market - Multiple wire connection at one pole POWER FORTONIC FORUM 19 settembre 2013 Wolfgang Sichmann Weidmüller Interface GmbH & Co. KG Slide 2

3 Introduction The trend for increasingly compact and powerful devices is generally met with higher voltages. While maintaining the same power level, current and connection cross-sections are kept within reasonable limits, which impacts positively on the size of the devices. However, higher voltages increase the requirements for clearance and creepage distances. Connection systems are inevitably following the trend for smaller sizes, which poses a challenge in relation to UL 1059 in particular. The UL 1059's strict regulations for field wiring components are absolutely justified, and illustrate the high demands on usage and handling. The aim here is to avoid mistakes in the field, or if mistakes have been made, to minimise the resulting damage. For the part of the connection system that is installed in the device in a secure manufacturing process, there is an option of approval with reduced clearance and creepage distances as part of the device (factory wiring). However, this means that the UL 1059 regulations also have to be observed in full for everything that is wired up or get connected in the field. With regard to the field connection, further differences to European usage and handling must also be taken into account. Topics such as multiple wire connections and wire-end ferrules underline the convergence but it also shows the differences between Europe and the US. POWER FORTONIC FORUM 19 settembre 2013 Wolfgang Sichmann Weidmüller Interface GmbH & Co. KG Slide 3

4 Difference between field and factory wiring Field wiring Plug or terminal with cable or single wires to connect field components Factory wiring Includes, for example, a plug-in connector, which is installed in the device during manufacturing in line with the applicable manufacturing guidelines. Example: By means of fastening and wiring By means on soldering to the PCB Field wiring = UL 1059 / factory wiring = UL 508(C) POWER FORTONIC FORUM 19 settembre 2013 Wolfgang Sichmann Weidmüller Interface GmbH & Co. KG Slide 9

5 UL 1059 application groups for terminals and plug-in connectors Use Group A: service devices Control and operating consoles Control and monitoring systems Use Group B: commercial appliances Cable-connected devices which are not permanently installed Use Group C: Industrial general All devices and systems for industrial applications Use Group D: Industrial limited ratings All devices and systems for industrial applications with limited current data Use Group E: 601 1,000 (1,500) volt Connection systems in the range of 601 to 1,500 volts back POWER FORTONIC FORUM 19 settembre 2013 Wolfgang Sichmann Weidmüller Interface GmbH & Co. KG Slide 10

6 UL 1059: clearance and creepage distances Table Limited ratings The spacings specified in item D of Table 8.1 are applicable to a terminal block for use only in or with industrial control equipment where the load on any single circuit of the terminal block does not exceed 15 A at V, 10 A at V, 5 A at V, or the maximum ampere rating, whichever is less. POWER FORTONIC FORUM 19 settembre 2013 Wolfgang Sichmann Weidmüller Interface GmbH & Co. KG Slide 11 back

7 Case 1: selection of a plug-in connector with corresponding requirements Example Component for field wiring Requirement up to 600 V Class C industrial general V UL 1059 rating data 35 A max. Rated voltage (use group B) Rated current (use group B) Rated voltage (use group C) Rated current (use group C) Rated voltage (use group D) Rated current (use group D) 600 V 35 A 600 V 35 A 600 V 5 A ok. Result: The field wiring component meets the requirements of UL Back to UL 1059 back POWER FORTONIC FORUM 19 settembre 2013 Wolfgang Sichmann Weidmüller Interface GmbH & Co. KG Slide 12

8 Case 2: Excerpt from catalogue or data sheet UL 1059 rating data Rated voltage (use group B) Rated current (use group B) Rated voltage (use group C) Rated current (use group C) Rated voltage (use group D) Rated current (use group D) To UL 1059 Through air distance 7.62 mm (0.3 inch) 6.9 mm (0.272 inch) 300 V 35 A 300 V 35 A 600 V 5 A? Example: Requirement up to 600 V Class C industrial general V 35 A max. Result: The requirements are not met for UL 1059 at V but are met for UL 1059 at V. Acc. to Table 8.1, UL 1059 for V we need a: Clearance of 9.5 mm Creepage 12.7 mm back POWER FORTONIC FORUM 19 settembre 2013 Wolfgang Sichmann Weidmüller Interface GmbH & Co. KG Slide 13

9 But the requirement is between volts?? What now?? Factory wiring The component assembled on the PCB can be jointly approved under device approval 508 (C) if the component fulfils the factory wiring criteria! Field wiring The counter part (field wiring component) must be approved under UL 1059! POWER FORTONIC FORUM 19 settembre 2013 Wolfgang Sichmann Weidmüller Interface GmbH & Co. KG Slide 14

10 Option of device approval via UL 508 / UL 840 for plug-in connectors on the PCB

11 Guide to device approval via UL 508 and UL 840 Component type test - clearance and creepage distance No UL 1059 Terminal Blocks UL 840 exception UL 508 / 508C No Alternative for PCB Components Standard Requirements Industrial Controls / Power Conversion Equipment UL 508A UL 840 exception No Standard Requirements Industrial Control Panels UL 840 exception UL 2011 No Standard Requirements Factory Automation Equipment NEC - National Electrical Code POWER FORTONIC FORUM 19 settembre 2013 Wolfgang Sichmann Weidmüller Interface GmbH & Co. KG Slide 16

12 Step 1: clearance UL V factory wiring (PCB connectors) UL 508 C Table 36.5 clearance distance = UL 1059 Therfore with UL 508 C exception via UL 840 insulation coordination for the clearance distance Pollution degree UL Overvoltage Category UL 840 Table 8.1 UL 840 Table 8.1 min. clearance - UL component type test clearance - connector larger pitch required No Clearance passed according to UL840 POWER FORTONIC FORUM 19 settembre 2013 Wolfgang Sichmann Weidmüller Interface GmbH & Co. KG Slide 17

13 Step 1/1: Finding the clearance distance Weidmüller type test: Lab report, clearance and creepage distance acc. to UL 1059 clearance! to Acc. to UL 1059 (600 V class C) or UL 508 (C) min. clearance = 9.5 mm min. creepage = 12.7 mm UL 1059 POWER FORTONIC FORUM 19 settembre 2013 Wolfgang Sichmann Weidmüller Interface GmbH & Co. KG Slide 18 back

14 Step 1/2: Finding the pollution degree UL Pollution Degree Pollution degrees based on the presence of contaminants and possibility of condensation or moisture at the creepage distance are as follows: Pollution Degree 1: No pollution or only dry, nonconductive pollution. The pollution has no influence. Pollution Degree 2: Normally, only nonconductive pollution. However, a temporary conductivity caused by condensation may be expected. Pollution Degree 3: Conductive pollution, or dry, nonconductive pollution that becomes conductive due to condensation that is expected. Pollution Degree 4: Pollution that generates persistent conductivity through conductive dust or rain and snow. back POWER FORTONIC FORUM 19 settembre 2013 Wolfgang Sichmann Weidmüller Interface GmbH & Co. KG Slide 19

15 power supply Overvoltage category Potential isolation Primary Supply Level Distribution Level Load Level Signal Level Overvoltage category IV Primary supply level Overvolt. category III Distribution level Overvolt. category II Load level Overvolt. category I Signal level Take lightning surge into account back Lightning surges do not have to be taken into account Permanent installation Take into account overvoltage caused by switching operations e.g. household devices No overvoltage taken into account Mainly operations with low voltages e.g. small electric devices POWER FORTONIC FORUM 19 settembre 2013 Wolfgang Sichmann Weidmüller Interface GmbH & Co. KG Slide 20

16 Step 1/3: UL 840 Table 8.1 minimum clearance UL 840 Section 8.9 Clearances selected and measured in accordance with the dimensions in Table 8.1 do not require testing. To type test to overvoltage to pollution back POWER FORTONIC FORUM 19 settembre 2013 Wolfgang Sichmann Weidmüller Interface GmbH & Co. KG Slide 21

17 Step 2: Creepage UL V factory wiring (PCB connectors) CTI of material (catalogue) Material Group UL840 (catalogue) 600 V Operating Voltage Pollution degree UL Table 9.1 UL840 min. creepage distance - UL component type test creepage distance -connector larger pitch required No Creepage distance according to UL840 POWER FORTONIC FORUM 19 settembre 2013 Wolfgang Sichmann Weidmüller Interface GmbH & Co. KG Slide 22

18 Step 2/1: Finding the creepage distance Weidmüller type test: Lab report, clearance and creepage distance acc. to UL 1059 creepage! min. Acc. to UL 1059 (600 V class C) or UL 508 (C) min. clearance = 9.5 mm creepage = 12.7 mm to UL1059 back POWER FORTONIC FORUM 19 settembre 2013 Wolfgang Sichmann Weidmüller Interface GmbH & Co. KG Slide 23

19 Step 2/2: UL 840 Table 9.3 Finding the pollution degree UL 840 section 9.3 Pollution Degree Pollution degrees based on the presence of contaminants and possibility of condensation or moisture at the creepage distance are as follows: Pollution Degree 1: No pollution or only dry, nonconductive pollution. The pollution has no influence. Pollution Degree 2: Normally, only nonconductive pollution. However, a temporary conductivity caused by condensation may be expected. Pollution Degree 3: Conductive pollution, or dry, nonconductive pollution that becomes conductive due to condensation that is expected. Pollution Degree 4: Pollution that generates persistent conductivity through conductive dust or rain and snow. back to creepage table back POWER FORTONIC FORUM 19 settembre 2013 Wolfgang Sichmann Weidmüller Interface GmbH & Co. KG Slide 24

20 Step 2/3: UL 840 Table 9.1 minimum creepage Link to pollution degree info 2 3 Material groups Group CTI I >600 II IIIa IIIb CTI of material PBT 200 Wemid 600 LCP 175 Creepage acc. to type test = 9.66 mm Creepage can not be less then over air distance ( 5.5mm) 6.9mm! to type test 1/2 to pollution degree 2/2 back POWER FORTONIC FORUM 19 settembre 2013 Wolfgang Sichmann Weidmüller Interface GmbH & Co. KG Slide 25

21 Summary of the solution for the PCB part of the connector using UL 508(C) and UL 840 New clearance distance 5.5 mm acc. to 508(C) & UL 840 Clearance O.K. Clearance distance according to UL840 No UL 508 (C) New Creepage creepage 3.2 distance mm acc.to 508(C) & UL 840 exception UL 840 exception UL 840 No UL 508A No UL 2011 O.K. exception UL 840 NEC National Electrical Code Creepage distance according to UL840 POWER FORTONIC FORUM 19 settembre 2013 Wolfgang Sichmann Weidmüller Interface GmbH & Co. KG Slide 26

22 The demand for increasingly compact connection systems makes this procedure necessary. job done! Factory wiring 600 V via UL 508 & UL 840 PCB part: Approval together with device approval UL 508(C) und UL 840. The component meets the clearance and creepage requirements for 600 Volt! Field wiring 600V UL 1059 class C Field part: No further action possible or necessary. The component meets the requirements of UL 1059 for 600 V! POWER FORTONIC FORUM 19 settembre 2013 Wolfgang Sichmann Weidmüller Interface GmbH & Co. KG Slide 27

23 Option of device approval via UL 508 / UL 840 for PCB terminals

24 Guide to device approval via UL 508 and UL 840 Component type test - clearance and creepage distance No UL 1059 Terminal Blocks UL 840 exception UL 508 / 508C No Alternative for PCB Components Standard Requirements Industrial Controls / Power Conversion Equipment UL 508A UL 840 exception No Standard Requirements Industrial Control Panels UL 840 exception UL 2011 No Standard Requirements Factory Automation Equipment NEC - National Electrical Code POWER FORTONIC FORUM 19 settembre 2013 Wolfgang Sichmann Weidmüller Interface GmbH & Co. KG Slide 29

25 Step 1: Clearance A (equivalency) UL V 9.5 mm clearance distance as per Table 7.1 UL 508 C Table 36.5 clearance = UL 1059 Therefore with UL 508C exception protection against stray strands (splicing) + UL 50 8C exception via UL 840 clearance A (equivalency) Table 7.1 UL 840 Table 7.1 Clearance A (Equivalency) No HV test positive larger pitch required Clearance according to UL840 back POWER FORTONIC FORUM 19 settembre 2013 Wolfgang Sichmann Weidmüller Interface GmbH & Co. KG Slide 30

26 Step 1/1: Finding the clearance distance Weidmüller type test: Clearance and creepage distance acc. to UL 1059 clearance! min. Acc. to UL 1059 (600 V class C) or UL 508 (C) min. clearance = 9.5 mm creepage = 12.7 mm back POWER FORTONIC FORUM 19 settembre 2013 Wolfgang Sichmann Weidmüller Interface GmbH & Co. KG Slide 31

27 Step 1/2: (replacement test for shorter clearance distances) Finding the test voltage UL Clearance A (Equivalency) 7.1 Other than as noted in 1.6, the requirements of this section may be used to evaluate clearances less than those specified for the end product while maintaining the same overvoltage withstand capability for the equipment. 7.2 A clearance, less than the specified minimum through air spacing, in the product standard, may be suitable if acceptable results are obtained when tested in accordance with Section 14, Dielectric Voltage-Withstand Tests, using a voltage with a value in accordance with Table 7.1 back POWER FORTONIC FORUM 19 settembre 2013 Wolfgang Sichmann Weidmüller Interface GmbH & Co. KG Slide 32

28 Step 2: Creepage UL V (PCB terminals) CTI of material (catalogue) Material group UL 840 (catalogue) 600 V Operating voltage Pollution degree UL Table 9.1 UL 840 min. creepage distance - UL component type test creepage distance connector larger pitch required No Creepage distance according to UL 840 POWER FORTONIC FORUM 19 settembre 2013 Wolfgang Sichmann Weidmüller Interface GmbH & Co. KG Slide 33

29 Step 2/1: Finding the creepage distance Weidmüller type test: Clearance and creepage distance acc. to UL 1059 creepage! Back Acc. to UL 1059 (600 V class C) or UL 508 (C) min. clearance = 9.5 mm min. creepage = 12.7 mm to table 9.1 2/4 back POWER FORTONIC FORUM 19 settembre 2013 Wolfgang Sichmann Weidmüller Interface GmbH & Co. KG Slide 34

30 Step 2/2: Finding the pollution degree UL Pollution Degree Pollution degrees based on the presence of contaminants and possibility of condensation or moisture at the creepage distance are as follows: Pollution Degree 1: No pollution or only dry, nonconductive pollution. The pollution has no influence. Pollution Degree 2: Normally, only nonconductive pollution. However, a temporary conductivity caused by condensation may be expected. Pollution Degree 3: Conductive pollution, or dry, nonconductive pollution that becomes conductive due to condensation that is expected. Pollution Degree 4: Pollution that generates persistent conductivity through conductive dust or rain and snow. Back to table 9.1 2/4 back POWER FORTONIC FORUM 19 settembre 2013 Wolfgang Sichmann Weidmüller Interface GmbH & Co. KG Slide 35

31 Step 2/3: UL 840 Table 9.1 minimum creepage Link to pollution degree info 2 3 Material groups Group CTI I >600 II IIIa IIIb CTI of material PBT 200 Wemid 600 LCP 175 to pollution degr. Creepage acc. to type test = 12,6 mm Creepage can not be less then over air distance (= 8.8mm)! to type test back POWER FORTONIC FORUM 19 settembre 2013 Wolfgang Sichmann Weidmüller Interface GmbH & Co. KG Slide 36

32 Summary: Possible dimensioning of clearance and creepage distances for UL 600 V Product standards UL 1059 requirements clearance / creepage > 9.5 mm for 600 V > 12.7 mm > 6.4 mm for 300 V > 9.5 mm UL 1059 OK for mm from lab. rep. OK for 300 V 9.66 mm from lab. rep. Device standards UL 508 (C) Alternative assessment (insulation coordination) UL 840 Table 9.1 UL 840 Material Group I ( Wemid ) Pollution degree 2 3 Through air 5.5 mm 5.5 mm requ. Creepage (3.2) 5.5mm 8.0 mm requ. OK 600 V OK 600 V Protection against 8.8 mm from lab. rep. > 6.4mm OK for 300 V + + > 9.5 mm 12.6 mm from lab. rep. stray for 300 V POWER FORTONIC FORUM 19 settembre 2013 strands Surge voltage test 10.7 kv no clearance measurement Creepage (3.2) 8.8 mm 8.8 mm requ. OK 600 V Acc. to UL 1059 (600 V Class C) or UL 5.08 (C) min. clearance = 9.5 mm min. creepage = 12.7 mm Wolfgang Sichmann Weidmüller Interface GmbH & Co. KG Slide 37

33 Wire-end ferrules for the American market Tools - The ferrules may only be used together with tested tools Twin wire-end ferrules - As they have not been approved, the use of twin wire-end ferrules are not allowed in either control or power circuits Wire-end ferrules for power circuits - All wire-end ferrules must be approved by UL - Can be used in field and factory wiring POWER FORTONIC FORUM 19 settembre 2013 Wolfgang Sichmann Weidmüller Interface GmbH & Co. KG Slide 38

34 Wire-end ferrules for the American market Wire-end ferrules in control circuits - Under factory wiring conditions and < AWG 14, wire-end ferrules may also be used without approval. For UL 508A - There is a UL guideline that permits the usage in control and power circuits under factory wiring conditions UL Usage as in UL 508A is planned UL 508C - No approval is planned for this at the moment POWER FORTONIC FORUM 19 settembre 2013 Wolfgang Sichmann Weidmüller Interface GmbH & Co. KG Slide 39

35 Multiple wire connection at one pole Multiple wire connection - the combination of the used connection system with the used conductors must always to be tested by UL Test - UL will test each combination with the full testing programme Wire cross-section and conductor type - Only conductors with the same cross-section and of the same type may be used Number of conductors per connection - The number of conductors approved by UL is indicated in the designation in brace before the wire cross-section e.g.: (4) AWG 12 str - This really does mean that only four conductors may be used. Two, three or more than four conductors are not permitted. POWER FORTONIC FORUM 19 settembre 2013 Wolfgang Sichmann Weidmüller Interface GmbH & Co. KG Slide 40

36 Any questions? Thank you! POWER FORTONIC FORUM 19 settembre 2013 Wolfgang Sichmann Weidmüller Interface GmbH & Co. KG Slide 41