





The LM Series MCU (microcontroller unit) LCD (liquid crystal display) Hour Meters and Counter are sealed digital instruments designed to monitor and record elapsed running time, normally displayed in hours and tenths of hours. These devices are used to log running time of equipment or counts of equipment use for potential use in transportation applications to assure proper maintenance of expensive machines or systems, as well as warranty claims and rental-use tracking.
- Diamond shape with bezel
- 2-hole mounting
- Running indicator
- Reverse polarity
- Load dump, inductive, and EMI transient immunity
- Makroblend® case material
- Lexan® lens
- 1/4 in. blade terminals
Product Codes | |
|---|---|
| Mfr Part No: | 70378425 |
Case depth: 1.35 in (including terminals)Digital range hours: 0 to 99,999.9 hours with auto turn overDigital range counts: 0 to 999,999 counts with auto turn overDigital height: 7 mmView angle: 12 o’clockAccuracy: ±200 ppm/hourOperating voltage range: 9 V to 64 V dc/ac (50 Hz to 500 Hz); 50 Hz for counter enableSealing: IP67 (front); IP66 (back)Shock: 55 g per SAE J1378; 75 g per MIL-M-3917DVibration: 20 g per SAE J1378; 10 g per MIL-M-3917DHumidity: 95 % non-condensing at 38 °C [100.4 °F]Operating temperature: -40 °C to 85 °C [-40 °F to 185 °F]Storage temperature: -50 °C to 90 °C [-58 °F to 190 °F]Power consumption: 0.8 mA @ 12 VdcStart time: <1 s; if including all “8†check, then >1 s
- Stock: Warehouse
- Manufacturer Part #: 70378425
Aircraft Fitment Finder
Returns & refund summary
- 30-day return window — with prior return authorization, unopened in original packaging.
- Restocking fee: 20% on unopened items, 30% on open-box items.
- Refund processing fee: 5.51% applies to all refunds (returns, cancellations, core-fee refunds) regardless of reason.
- Return shipping: paid by buyer.
- Non-returnable categories: installed/used parts, special-order or rebuilt items, programmed items (incl. ELTs), batteries, AOG-priority orders, international orders.
Full terms: Return Policy.
Authenticity & authorization
All parts sold by American Aviation Parts are genuine factory products sourced through authorized distribution channels. Our authorization status varies by brand — for some brands we are a direct authorized dealer; for others we are an independent reseller through authorized distribution. Either way, the part you receive is the same factory product, with standard documentation available on request.
See our full Manufacturer Authorizations page for the current per-brand status.
Need traceability paperwork?
If your installation requires FAA Form 8130-3, manufacturer Certificate of Conformance, or other traceability documentation, please call 1-877-722-8727 or email [email protected] before placing the order so we can confirm what is available for this part.
Shipping
Standard ground, expedited, and AOG shipping options are available at checkout. Full shipping-cost tiers and timelines are published on our Delivery Information page.