See http://www.mikrocontroller.net/topic/311445 for photos, diagrams and tips. Note: some numbers and names (e.g. polarity of rectifiers) are not consistent: c1 K1 big contactor c2 d1 K2 small contactor e3 / e5 6,3A / 8,0A fuse k / k1 power inductor m1 / m3 fan motor / big transformer m4 / m6 in diagram, but not in spare parts list numbers of contactor contacts (a1/1/4, a1/2/V, u1) I will add a list later. polarity of rectifiers V1 and n2 wire motor (both stator and rotor) is driven from AC in s0000035-00.pdf Appended files: s0000035-00.pdf S00.0003.5-00 Stromlaufplan Steuerplatte SH 140 s0000081-00.pdf S00.0008.1-00 SH 140 L, Blockschaltbild, Hauptbauteile nach Blockschaltbild U1 Platine FTE SH140L (große Grundplatine - big backplane board) u1/kl1 (KL1) 1 no connection 2 | c1/13 via 2,5A fuse to 42V trafo's primary and fan 3 | from mains cable 4 | c1/23 5 no connection 6 | c1/33 to 42V trafo's primary and fan 7 | from mains cable 8 | c1/43 9 no connection 10 common 0V c1/a kl2/1 b1/10 b3/1 d1/b 11 | 42V ac c1/83 b1/7 b1/11 from 42V-trafo via 2,5A fuse 12 | 42V ac to burner's momentary push button 13 b1/2 from motor-speed-trafo via e5 6,3A / 8,0A fuse 14 b1/3 from motor-speed-trafo 15 b1/4 d1/41 to wire motor's rotor 16 d1/42 d1/34 to wire motor's rotor 17 b3/3 42V ac from burner's momentary switch (Brennertaster) b10 18 d1/14 kl1/22 b3/11 19 b3/8 from 5-step switch a1/9 20 b3/9 from 5-step switch a1/13 21 b3/10 from 5-step switch a1/10 22 b3/11 from 5-step switch a1/14 kl1/18 d1/14 23 b1/9 to wire motor's stator 24 b1/12 to wire motor's stator u1/kl2 (KL2, L2) 1 common 0V to gas valve 2 c1/84 to gas valve 3 no connection 4 | c1/44 5 | output to power selector switch / trafo 6 | c1/34 7 no connection 8 | c1/24 9 | output to power selector switch / trafo 10 | c1/14 b1 U2 rectifier board FTE DF140 60.505 (near big contactor c1 DSL6-62) 1 dc1 + d1/33 SH (Siemens & Halske) E2620 055 B 125 C 5000/3300 B125C5000/3300 n2 to collector (rotor) of wire motor 2 ac1 ~ kl1/13 from motor-trafo / speed switch 3 ac1 ~ kl1/14 from motor-trafo / speed switch 4 dc1 - kl1/15 d1/41 Frako (Frankfurter Kondensatorenwerk) KE47µ 100V (KE 47µF 100V) to collector (rotor) of wire motor 5 dc2 + d1/24 f (Fagor ?) B125 C1500R B125C1500R n4 6 ac2 ~ c1/b to coil of big contactor c1 7 ac2 ~ b1/11 c1/83 kl1/11 kl1/12 42V ac 8 dc2 - b3/6 d1/23 Frako (Frankfurter Kondensatorenwerk) KE47µ 100V (KE 47µF 100V) K3 9 dc3 + kl1/23 f (Fagor ?) B125 C1500R B125C1500R n3 to field (stator) of wire motor 10 ac3 ~ common 0V 11 ac3 ~ b1/7 c1/83 kl1/11 kl1/12 42V ac 12 dc3 - kl1/24 Frako (Frankfurter Kondensatorenwerk) KE47µ 100V (KE 47µF 100V) to field (stator) of wire motor b3 X1 U3 timing board FTE ST140 (near small contactor d1 DSL4-31) 1 common 0V 2 no connection 3 kl1/17 from burner's momentary switch (push button) 4 no connection 5 d1/a to coil of small contactor d1 6 d1/23 b1/8 7 d1/13 8 kl1/19 a1/ 9 9 kl1/20 a1/13 10 kl1/21 a1/10 11 kl1/22 kl1/18 d1/14 a1/14 12 no connection c1 (K1) big contactor Westinghouse Fanal Schütz DSL6-62 (6 closing + 2 opening contacts) a kl1/10 common 0V b b1/6 13 kl1/2 kl1/3 kl1/4 14 kl2/8 kl2/9 kl2/10 23 kl1/2 kl1/3 kl1/4 24 kl2/8 kl2/9 kl2/10 33 kl1/6 kl1/7 kl1/8 34 kl2/4 kl2/5 kl2/6 43 kl1/6 kl1/7 kl1/8 44 kl2/4 kl2/5 kl2/6 53 nc 54 nc 61 nc 62 nc 71 nc 72 nc 83 kl1/11 kl1/12 etc. 42V ac 84 kl2/2 to gas valve d1 (K2) small contactor Westinghouse Fanal Schütz DSL4-31 (3 closing + 1 opening contacts) attention: some types have different contact layout: 13-14 23-24 33-34 41-42 or 13-14 23-24 41-42 33-34 a b3/5 b common 0V 13 b3/7 from 5-step-switch a1/14 14 b3/11 kl1/18 kl1/22 from 5-step-switch a1/14 23* b1/8 b3/6 - of the middle rectifier and capacitor to activate c1(big contactor)'s coil 24* b1/5 + of the middle rectifier and capacitor to activate c1(big contactor)'s coil 33 b1/1 wire motor run 34 d1/42 kl1/16 wire motor run 41 b1/4 kl1/15 wire motor break (short rotor) 42 d1/34 kl1/16 wire motor break (short rotor) * these contacts were burnt (because they short the middle 47µF capacitor) so I had to exchange this contactor Hauptbauteile nach Blockschaltbild a1 5-Stufen-Schalter 16.116 5-step mode switch b1 Betriebswahlschalter 16.250 (auch a2 genannt) 6-step current and wire speed switch b10 Brennerschalter siehe Brenner b11 CO2 +/- selector varies wire speed c1 Hauptschütz 14.900 (auch K1 genannt) big contactor DSL6-62 d1 Steuerrelais 14.902 (auch K2 genannt) small contactor DSL4-31 e1 Steuersicherung 2,5A 25.303 fuse (upper) for 42V primary and fan e2 Steuersicherung 2,5A 25.303 fuse (middle) for 42V secondary e3 Steuersicherung 8,0A 25.310 fuse (lower) for wire motor m5 (inconsistency: not for m3 (fan)) e4 Thermoschalter T177° 402-6067 402-60 67 300 F8 VDE K over-temperature switch (glued onto big transformer) e5 Motorsicherung 6,3A / 8,0A (inconsistency: not for m3 (fan)) h1 Kontrollampe 130V 25.001 power on indicator k1 Drossel 12.161 power inductor m1 big transformer 140A (inconsistency with m3 fan motor) m2 Steuertrafo 14.700 42V transformer m3 Schweißtrafo 12.060 big transformer 140A (inconsistency: fan motor) m4 Motor-Geschwindigkeitsregler motor speed potentiometer m5 Gleichstrommotor 42V 34.120 wire motor 42V m6 Motor-Geschwindigkeitstrafo motor speed transformer n1 Schweißgleichrichter 14.610 big rectifier 140A s1 Gasventil 16.470 gas valve 42V u1 Steuerung komplett 78.015 main backplane board (complete) u2 Motorsteuergleichrichter 78.001B rectifier board u3 Schweißtakter 78.020 timer board Schaltstellungen des a1 (5-Stufen-Schalter) Betriebsart (mode of operation) Schweißen (weld) Aus (off) Intervall 1 kurz Intervall 2 lang Punkten (one time) a1 1 2 3 4 5 R 1/4 X X X X S 2/V X X X X 14 10 X 9 10 X X 14 13 X Schaltstellungen des a2 (oben b1 Betriebswahlschalter genannt) für Schweißstom und Drahtgeschwindigkeit (welding current and wire speed) a2 1 2 3 4 5 6 R 4 U1 X R 5 U2 X R 6 U3 X R 7 U4 X R 8 U5 X R 9 U6 X S 6 V1 X S 5 V2 X S 4 V3 X S 3 V4 X S 2 V5 X S 1 V6 X