Electrical Box: L4 for J, H, HJ Operators parts
LiftMaster Electrical Box Parts — L4 for J, H and HJ Operators
Genuine replacement parts for the Logic Control Version 4 electrical box fitted to LiftMaster J jackshaft, H hoist and HJ hoist-jackshaft industrial operators.
L3 or L4? The enclosure and internal layout are the same on both. The difference is the logic board — L4 uses the K001A6837. Read the part number printed on the board itself if you are not sure. The L3 page for J, H and HJ carries the exploded diagram, and the component positions are identical.
Single-phase and three-phase machines take different C relays — ref 6 below. Check the data label before ordering. Parts marked no longer available have been discontinued and are listed for identification only.
Single Phase or Three Phase?
| Supply | C Relay | Notes |
|---|---|---|
| 1 phase | 29-31229 — 24VDC SPDT | C relay only |
| 3 phase | 29-31245 — 12VDC SPDT | Serves both C and D positions |
Box Components
| Ref | Part # | Description |
|---|---|---|
| 3 | K75-35626 | Cover (no longer available) |
| — | K75-36913 | E-Box Cover — R, J, H, HJ and L5. The current cover for these operators |
| 4 | 21-14182 | Transformer, 115/230V (K21-14182) |
| 4 | K21-35057 | Transformer, 460V |
| 4 | 21-35077 | Transformer, 575V (K21-35077) |
| 5 | 29-31244 | Relay, 24VDC DPST — A and B relay, all operators (K29-31244) |
| 6 | 29-31229 | Relay, 24VDC SPDT — C relay, single phase only |
| 6 | 29-31245 | Relay, 12VDC SPDT — C and D relay, three phase only |
| 7 | K74-31243 | MOV, 580V — surge protection |
| 8 | K79-15016-1 | RPM Sensor Assembly |
| 12 | 42-31246 | Terminal Block, 3 position 600V 20A (K42-31246) |
| 13 | 42-10040 | Terminal Block, radio (K42-10040) |
Logic Board & Radio
| Ref | Part # | Description |
|---|---|---|
| 9 | K001A6837 | Logic Board, L4 (no longer available) |
| — | TLS1CARD | Logic 4 Option Board |
| 10 | K2A761 | Coaxial Cable (K002A0761) |
| 11 | K1C3196-3 | Antenna (109186) |
Limit Shaft & Switch Kits — K Groups
| Ref | Part # | Description |
|---|---|---|
| K1 | K72-14130-1 | Limit Shaft Kit — complete assembly |
| K2 | K72-12515-1 | Limit Switch Kit |
Other Electrical Box Versions
L3 for J, H, HJ · L4 for T, GT, GH · L3 for T, GT, GH · Logic Control Version 2