LG HDF-2 HDF-1 Display

LG HDF-2 HDF-1
3R36905A PCB(UPPER)
3R36904A PCB(BELOW)
3R35345B (DISPLAY)
ASY:2R21970B

Ordering the lg hdf-2 hdf-1

To order the lg hdf-2 hdf-1, send us a photograph of the existing unit and its nameplate at [email protected]. Please quote the complete code including any revision suffix so that our team can confirm the correct variant, current stock and lead time before you commit.

About the lg hdf-2 hdf-1

Elevator and escalator installations are built around a relatively small number of serviceable assemblies, but they fail at very different rates. The lg hdf-2 hdf-1 sits in the switches / sensors / wiring group, and it is replaced on a different service interval from the assemblies around it. In practice the failures we see on lg hdf-2 hdf-1 come down to contact pitting, moisture ingress at the cable gland, drifted optical alignment, and brittle insulation on travelling cables after years of flexing.

Every lg hdf-2 hdf-1 we supply is inspected before dispatch. Each unit is checked for physical damage, correct marking and the specific wear or degradation patterns that matter for this class of component, then packed to survive international transit. Where a superseded revision is the only one available, we say so plainly and explain the substitution, so the installing engineer can make an informed decision rather than discovering the difference on site.

Buying guidance and compatibility notes

Before ordering the lg hdf-2 hdf-1, confirm three things. First, the switch or sensor model, the mounting pattern, and the supply voltage and contact configuration (NO or NC). Second, contact configuration matters more than physical size — a switch that bolts straight on can still be electrically wrong. Third, whether the installation is a traction lift or an escalator, since duty cycle and loading differ between the two.

On fitting, one point is worth repeating: record the terminal numbers before disconnecting a travelling cable, since colour codes are not consistent between controller generations. Almost every repeat failure we see on lg hdf-2 hdf-1 traces back to a related component that was left in place, or to an adjustment that was assumed rather than measured.

Moisture is the most common cause of premature failure in lift electrics. A gland that is not quite tight, a conduit that fills with condensate, or a shaft that lets in driving rain will eventually find its way into the least protected component in the circuit.

The underlying cause is usually moisture finding its way in through a gland that is not quite tight, which is why inductive switching duty shortens contact life dramatically compared with a resistive load of the same rating.

Earth leakage and insulation resistance are worth measuring whenever an electrical fault is investigated. A component that tests fine in isolation can be part of a circuit whose insulation has degraded to the point of intermittent failure under load.

Sensing and switching devices decide whether the controller can trust what it is told; the shaft environment is harsher than the machine room, so a component that tests correctly on a dry day can still fail in service.

If you are unsure which variant of the lg hdf-2 hdf-1 you need, send a photograph of the nameplate and the existing component alongside a description of the fault. That is usually enough for our team to identify the correct replacement without a site visit, and it avoids the cost and delay of returning an incompatible part. We are also happy to advise on the other serviceable items in the same switches / sensors / wiring group, so a planned shutdown can cover several wear items at once.

Related parts and further reading

Because lg hdf-2 hdf-1 is only one item in the switches / sensors / wiring group, these related pages may help you plan the work:

• Elevator limit switches
• Elevator Levelling Sensor
• Elevator Encoder
• Elevator Push Button
• Elevator Display

Reference sources

The compatibility information on this page was cross-checked against the following authoritative references. Always confirm the exact reference against your own equipment nameplate.

• ISO 8100-1 — lift safety standard
• IEC — electrical equipment standards
• Otis electrical components reference