MODELS: WD-52627 / 52628 / 62627 / 62628 / 62827 / 62927 / 73727 / 73827 / 73927

Using Lead Free Solder

Pb Solder

 

 

• The flux is more corrosive.

 

 

 

 

 

 

 

 

 

 

• The time required for a good solder connection may

The above symbol indicates Lead (Pb) Free solder was

 

take longer.

 

 

 

used during the construction of PWBs. Only Lead

 

• Poor wet-ability can cause solder balls.

Free solder should be used when servicing these

 

• Higher temperatures can cause flux spattering.

PWBs.

 

 

• Soldering iron tip life is shortened.

 

 

 

• Dull finish solder joints (not shiny) can appear to be

Solder must be compatible with that used by the

 

a “cold” solder joint.

 

 

manufacturer. Leaded solder can not be used on

In general a tip temperature of 700° F will usually provide

PWBs manufactured with Pb-free solder. The Mitsub-

ishi standard for service requires the use of Tin-Silver-

good results.

 

 

 

Copper (Sn-96.5, Ag-3.0, Cu-0.5). It can be obtained

 

 

 

 

 

through the Parts Department.

 

Displays used to indicate Pb-free

Order part number: PB FREE SOLDER

 

 

PCBs will be marked, indicating the level of Pb-free con-

 

 

Lead Free solder has a higher melting point, and does

struction. Table 1 defines the levels by phase and shows

not “wet” as well as leaded solder. This means it does

the different symbols that will be displayed on the PCB.

not adhere as readily to the solder iron tip, and the

Additionally, a PCB constructed using Pb-free solder may

surface to be soldered. To counteract this, the flux

be simply marked LFS.

 

 

used is more corrosive.

 

When possible, the indication will be placed close to the

 

 

The following cautions must be taken when using Pb

part number that is screened onto the PCB (not the part

Free solder.

 

label). Figure 1 is an example of a PCB showing the

• Higher temperatures can cause the PWB to

display and its location.

 

 

warp, detaching surface mount

 

 

 

 

 

 

Pb-Free

 

 

 

Short Display (When the

components.

 

 

 

Phase

Definition

Display

area is too small)

 

• Higher temperatures may

Phase-1 PCB's constructed using

Solder

Pb S

cause thermal damage to

Pb-free solder.

Pb

components.

 

 

 

 

 

 

Higher temperatures can cause

plastics, such as connectors,

Phase-2

Solder, PCB surface

 

 

 

 

relays, LEDs electrolytic

 

finishing and component

Pb

Joints

Pb

J

 

lead plating is Pb-free.

capacitors, etc. to melt or

 

 

Components may have

 

 

 

 

warp.

 

internal Pb.

 

 

 

 

• Higher temperatures can cause

Phase-3

Solder, PCB surface

 

 

 

 

surface oxidation resulting in

 

finishing and components

Pb

PCA

Pb

P

 

are Pb-free. (100% Pb-

poor solder spread-ability and

 

 

 

 

 

wet-ability.

 

free)

 

 

 

 

 

Table 1: Pb-Free Phases and Symbols

 

 

 

 

 

 

Pb-Free

 

 

 

 

 

 

Display

 

 

 

 

 

 

Figure 2: Pb-Free display on PWB

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Mitsubishi Electronics V30+, V31 CHASSIS, V29 specifications Displays used to indicate Pb-free, Pb-Free Display