Fluke 1587 FC vs Fluke 287: Which Is Better for Electrical Diagnostics?

Specs side by side

Specs checked against manufacturer documentation and official Amazon listings. Desk research, not bench testing. How we research.

Key differences

• →Only the 1587 FC can stress insulation with a test voltage (50 to 1000 V) and report megohms and gigohms; the 287 has no insulation function.
• →The 287 records unattended in its own memory with a real-time clock and graphs the trend on screen; the 1587 FC sends its readings and PI/DAR graphs to the Fluke Connect app instead.
• →Current is lopsided: the 287 covers 0.01 µA resolution through 10 A, while the 1587 FC stops at 400 mA with no 10 A jack.
• →The 287 resolves finer: 50,000 counts and ±(0.025% + 2) DC volts against 6,000 counts and ±(0.09% + 2).
• →The 1587 FC has a low-pass filter for drive outputs; the 287 does not (Fluke reserves that for the 289).
• →Safety category is identical: both are CAT IV 600V / CAT III 1000V.

Power on or power off: where each meter enters a diagnosis

Most electrical diagnoses have two halves. While equipment is running you collect symptoms: a voltage that sags when a compressor starts, a current that creeps up over a shift, a control signal that drops out once an hour. After you shut it down and lock it out, you confirm a cause: a winding that has absorbed moisture, a cable whose jacket has cracked, a terminal that has tracked to ground. The 287 is designed for the first half. The 1587 FC is designed for the second.

That split explains almost every spec difference below. An insulation tester must hold steady test voltage into a cable and then discharge it safely, so the 1587 FC spends its design budget there and keeps the meter side to 6,000 counts and milliamps. A logging meter must sit on a live panel for a long time and capture what happens, so the 287 spends its budget on a large graphic screen, deep memory, six AA cells and a wide current range. If your work regularly includes both halves, the honest answer is that you will eventually own both kinds of instrument.

The numbers side by side

The resistance chart needs a caution. The 287's 500 MΩ range can look like an insulation reading, but it comes from the ordinary ohms circuit, which drives only a small voltage through the part. A winding with damp or contaminated insulation can look fine at that level and still break down when a few hundred volts are applied, which is the condition a motor sees in service. That is the gap the 1587 FC's 250, 500 and 1000 V test positions close. Fluke publishes the 287's high-ohm range, not a test voltage for it, so treat it as a continuity-class check, not proof of insulation.

Current measurement shapes the toolkit

On the 287 you can put the meter in series with a load up to 10 A, read a 4–20 mA loop on the 50 mA range at 0.001 mA steps, or drop to the 500 µA range for a standby drain at 0.01 µA. Fluke publishes the burden on that microamp range as 102 µV per µA, so you can work out how much the meter itself disturbs a low-voltage circuit. With logging switched on, the same current ranges can record a compressor's draw across a whole cycle.

The 1587 FC offers just two current ranges, 60 mA and 400 mA, protected by a 0.44 A fuse. That covers control circuits and sensor loops, not motor current. Kits that bundle the 1587 FC with Fluke's i400 current clamp are separate Amazon listings; the one we link is the bare meter. If running current is part of most of your calls, pair the 1587 FC with a clamp meter (our clamp meter buying guide covers the choice) or look at a 10 A meter.

Two kinds of record keeping

Both meters let you keep evidence, but the evidence looks different. The 287 writes interval and event records into its own memory, stamped by a real-time clock, and draws them as a TrendCapture graph you can scroll and zoom on the meter. Fluke's manual sets the ceiling at 10,000 sample intervals, with event records sharing a 15,000 total; Fluke's product page words it two ways ("up to 10,000 readings" and "up to 15,000 recorded events"), which matches the manual's split between intervals and events. Full records leave the meter over an IR cable into FlukeView Forms on a PC.

The 1587 FC keeps its history in the Fluke Connect app over a 2.4 GHz radio. What it stores is less about minute-by-minute behavior and more about asset condition: a 1-minute insulation value, a PI or DAR ratio with its TrendIt graph, and the same test repeated next quarter with temperature compensation so a cold morning and a hot afternoon can be compared fairly. That is maintenance-history data. For what PI and DAR mean and how to read them, see Fluke 1587 FC vs Fluke 87V; for the 287's event records on an intermittent fault, see Fluke 287 vs Fluke 87V.

Live diagnostics on drives and electronics

One result surprises people. On a variable-frequency drive output, the insulation meter is the one with the better tool: a low-pass filter that blocks the high-frequency switching so the voltmeter shows the fundamental the motor responds to. Fluke's 287/289 manual lists that filter as "Model 289 only," so the 287 has none, and neither has LoZ. If you troubleshoot drive-fed motors and also want logging, the Fluke 289 vs Fluke 287 page explains what the extra money buys.

On control boards and instrumentation, the 287 pulls well ahead: 0.01 Ω steps on its 500 Ω range, capacitance from 1 nF to 100 mF, duty cycle and frequency to 999.99 kHz, and a 250 µs peak capture for brief spikes. The 1587 FC covers capacitance to 9,999 µF and frequency to 99.99 kHz, which handles motor-run capacitors and line frequency but not much finer electronics work. Temperature favors the 1587 FC in one way: Fluke includes a K-type thermocouple, while our sources don't state that the 287 ships with one.

Which should you buy?

If insulation testing is the main reason you are shopping and you only need 500 V and 1000 V, the Fluke 1577 vs Fluke 1587 FC comparison covers the simpler model. If you work outdoors or in wet plants, read Fluke 1587 FC vs Fluke 87V MAX, since the 1587 FC is only IP40. For a broader list of meters by trade, see the best multimeters for electricians and our guide to checking a motor winding for a short.

Frequently asked questions