The components of a SPD: Difference between revisions

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The SPD chiefly consists of (see {{FigRef|J48}}):<br>1)&nbsp; one or more nonlinear components: the live part (varistor, gas discharge tube, etc.);<br>2)&nbsp; a thermal protective device (internal disconnector) which protects it from thermal runaway at end of life (SPD with varistor);<br>3)&nbsp; an indicator which indicates end of life of the SPD;<br>Some SPDs allow remote reporting of this indication;<br>4)&nbsp; an external SCPD which provides protection against short circuits (this device can be integrated into the SPD).
The SPD chiefly consists of (see {{FigRef|J48}}):


[[File:Fig J45.jpg|none]]
'''1)''' one or more nonlinear components: the live part (varistor, gas discharge tube, etc.);
'''''Fig. J48:''' Diagram of a SPD''


== Technology of the live part''<br>'' ==
'''2)''' a thermal protective device (internal disconnector) which protects it from thermal runaway at end of life (SPD with varistor);
 
'''3)''' an indicator which indicates end of life of the SPD;
: Some SPDs allow remote reporting of this indication;
 
'''4)''' an external SCPD which provides protection against short circuits (this device can be integrated into the SPD).
 
{{FigImage|DB422510|svg|J48|Diagram of a SPD}}
 
== Technology of the live part ==


Several technologies are available to implement the live part. They each have advantages and disadvantages:  
Several technologies are available to implement the live part. They each have advantages and disadvantages:  
*Zener diodes;  
*Zener diodes;  
*The gas discharge tube (controlled or not controlled);  
*The gas discharge tube (controlled or not controlled);  
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The table below shows the characteristics and the arrangements of 3 commonly used technologies.  
The table below shows the characteristics and the arrangements of 3 commonly used technologies.  


{| class="wikitable"
{{TableStart|Tab1302|5col}}
|-
|-
! Component  
! Component  
! Gas Discharge Tube (GDT)  
! Gas Discharge Tube (GDT)  
! Encapsulated spark gap  
! Encapsulated spark gap  
! Zinc oxide varistor&nbsp;<br>
! Zinc oxide varistor
! GDT and varistor in series
! GDT and varistor in series
! Encapsulated spark gap and varistor in parallel
! Encapsulated spark gap and varistor in parallel
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|-
|-
| {{Table_HC2}} |
| {{Table_HC2}} |
| valign="middle" | [[File:Fig J46a.jpg|center|59x128px]]
| valign="middle" | [[File:DB422511.svg]]
| valign="middle" | [[File:Fig J46b.jpg|center|59x123px]]
| valign="middle" | [[File:DB422512.svg]]
| [[File:Fig J46c.jpg|center]]  
| [[File:DB422513.svg]]  
| [[File:Fig J46d.jpg|center|39x139px]]  
| [[File:DB422514.svg]]  
| [[File:Fig J46e.jpg|center|146x150px]]
| [[File:DB422515.svg]]
|-
|-
| {{Table_HC2}} | '''Operating mode'''  
| {{Table_HC2}} | '''Operating mode'''  
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|-
|-
| {{Table_HC2}} | '''Operating curves'''  
| {{Table_HC2}} | '''Operating curves'''  
| valign="middle" align="center" colspan="2" | [[File:Fig J46f.jpg|center]]  
| valign="middle" align="center" colspan="2" | [[File:DB422516.svg]]
| valign="middle" align="center" | [[File:Fig J46g.jpg|none]]
| valign="middle" align="center" | [[File:DB422517.svg]]
| {{Table_HC2}} |
| {{Table_HC2}} |
| {{Table_HC2}} |
| {{Table_HC2}} |
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| Type 1+ Type 2  
| Type 1+ Type 2  
| Type 1+ Type 2
| Type 1+ Type 2
|}
|-
 
{{TableEnd|Tab1302|J49|Summary performance table}}
'''''Fig. J49:''' Summary performance table''


'''Note:''' Two technologies can be installed in the same SPD (see {{FigRef|J50}})
'''Note:''' Two technologies can be installed in the same SPD (see {{FigRef|J50}})


{{Gallery|J50|The Schneider Electric brand iPRD SPD incorporates a gas discharge tube between neutral and earth and varistors between phase and neutral|221px|
{{Gallery|J50|The Schneider Electric brand iPRD SPD incorporates a gas discharge tube between neutral and earth and varistors between phase and neutral|215px|
|PB116777.jpg||
|PB116777.jpg||
|DB422518.svg||
|DB422518.svg||}}
}}


[[zh:浪涌保护器的部件]]
[[zh:浪涌保护器的部件]]

Revision as of 00:42, 5 December 2016


The SPD chiefly consists of (see Fig. J48):

1) one or more nonlinear components: the live part (varistor, gas discharge tube, etc.);

2) a thermal protective device (internal disconnector) which protects it from thermal runaway at end of life (SPD with varistor);

3) an indicator which indicates end of life of the SPD;

Some SPDs allow remote reporting of this indication;

4) an external SCPD which provides protection against short circuits (this device can be integrated into the SPD).

Fig. J48 – Diagram of a SPD

Technology of the live part

Several technologies are available to implement the live part. They each have advantages and disadvantages:

  • Zener diodes;
  • The gas discharge tube (controlled or not controlled);
  • The varistor (zinc oxide varistor).

The table below shows the characteristics and the arrangements of 3 commonly used technologies.

Component Gas Discharge Tube (GDT) Encapsulated spark gap Zinc oxide varistor GDT and varistor in series Encapsulated spark gap and varistor in parallel
Characteristics
DB422511.svg DB422512.svg DB422513.svg DB422514.svg DB422515.svg
Operating mode Voltage switching Voltage switching Voltage limiting Voltage-switching and -limiting in series Voltage-switching and -limiting in parallel
Operating curves DB422516.svg DB422517.svg
Application
  • Telecom network
  • LV network

(associated with varistor)

LV network LV network LV network LV network
SPD Type Type 2 Type 1 Type 1 or Type 2 Type 1+ Type 2 Type 1+ Type 2
Fig. J49 – Summary performance table

Note: Two technologies can be installed in the same SPD (see Fig. J50)

zh:浪涌保护器的部件

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