1.3

General notes on soldering

Permissible heat exposure loads on film capacitors are primarily characterized by the upper cate-

can lead to changes in the plastic dielectric and thus change irreversibly a capacitor's electrical

characteristics. For short exposures (as in practical soldering processes) the heat load (and thus

the possible effects on a capacitor) will also depend on other factors like:

Pre-heating temperature and time

Forced cooling immediately after soldering

Terminal characteristics:

diameter, length, thermal resistance, special configurations (e.g. crimping)

Height of capacitor above solder bath

Shadowing by neighboring components

Additional heating due to heat dissipation by neighboring components

Use of solder-resist coatings

The overheating associated with some of these factors can usually be reduced by suitable coun-

termeasures. For example, if a pre-heating step cannot be avoided, an additional or reinforced

cooling process may possibly have to be included.

EPCOS recommends the following conditions:

Pre-heating with a maximum temperature of 110

°C

Temperature inside the capacitor should not exceed the following limits:

MKP/MFP 110

°C

MKT 160

°C

When SMD components are used together with leaded ones, the leaded film capacitors should

not pass into the SMD adhesive curing oven. The leaded components should be assembled af-

ter the SMD curing step.

Leaded film capacitors are not suitable for reflow soldering.

Uncoated capacitors

For uncoated MKT capacitors with lead spacings

≤10 mm (B32560/B32561) the following mea-

sures are recommended:

pre-heating to not more than 110

°C in the preheater phase

rapid cooling after soldering

B32632 ... B32634

Very high pulse (wound)

Page 21 of 29

Please read Cautions and warnings and

Important notes at the end of this document.