Pilot Light Selection Guide
Pilot lights are divided into monobloc, contact-block, Ba9S lamp holder, buzzer, indicator and DIN rail types; the choice depends on the structure of the light source.
This guide covers what to look at when choosing products in the Pilot Lights category.
Pilot light types
- Monobloc LED lamps: the light source and housing are a single piece, made for a specific voltage (such as the EMAS MB series).
- Contact-block (modular) lamps: the front element, holder and LED block are separate parts; the light source is renewed by replacing the block (such as the EMAS CP and CM series).
- Ba9S lamp holder lamps: the light source is a bulb or LED bulb that fits into the lamp holder and can be replaced separately.
- Types with buzzer: gives an audible alarm in the pilot light housing, and illuminated models are also available; the sound level appears in product names as 90 dB.
- Types with indicator: voltmeter pilot lights and ammeter pilot lights, which show voltage or current as digits in a 22 mm housing, are in separate subcategories.
- DIN rail modular lamps: ABB E219 models are fitted not on the enclosure door but in the circuit breaker row inside the enclosure.
Multi-tier stack lights and beacons that must be seen from a distance are in Stack Lights and Warning Lights, and motorized sirens are in Warning Devices and Sirens.
What to look at when choosing a pilot light
- Mounting diameter: most products fit a 22 mm hole; there are also 16 mm and 30 mm models, and 10 mm and 14 mm lamps in the EMAS S series.
- Voltage and current type: a lamp whose name says "24 V AC/DC" works on both alternating and direct voltage, and one that says "230 V AC" works on alternating voltage only. Wide-range models such as 12-30 V AC/DC or 100-230 V AC are also listed. The lamp voltage must be the same as the control circuit voltage; for a 24 V DC control supply, see the Power Supplies category.
- Protection rating: values such as IP40, IP50, IP54, IP65 and IP69K appear in product names and data. The value is for the front face of a lamp mounted on the enclosure; in ABB product data, IP66, IP67 and IP69K are written separately for the front face and IP20 for the terminals.
- Front element: there are plastic and metal framed, flat or honeycomb-lens, round, square and rectangular models.
Complete lamp or single part
In modular series, both complete lamps and single parts are listed in the same category. When the product name is not enough, check the code and the supplied components in the product data.
- Siemens: the name of products with 3SU11 and 3SB6 codes states the voltage. Products with the 3SU10 code are the head only; the product data states that the holder, contact and LED module are selected separately. The data of the 16 mm 3SB2 models states that the lamp holder and a 24 V bulb are included.
- ABB: products with the ML1 code are lamp heads, and products with the MCBH code are holders. Compact lamps with the CL-100 code have a Ba9S lamp holder; confirm before ordering whether the bulb comes with the product. Models with the CL2 code have a built-in LED.
- Schneider Electric: for products whose code starts with ZB or whose name contains "body", verify the scope from the manufacturer's data.
Spare LED blocks, Ba9S bulbs and lamp heads are in the Push Button and Pilot Light Accessories and Spare Parts category.
How to read color and voltage from the product code
- Schneider Electric XB4, XB5 and XA2: in the code, the B after the letter V indicates a 24 V AC/DC supply and M indicates a 220-230 V AC supply, and the digit that follows indicates the color: 1 white, 3 green, 4 red, 5 yellow or orange, 6 blue. By this reading, XB4BVM4 is a 230 V AC red lamp. Codes with a 6 after the letter V (such as XB5AV64) are the direct-supply type that appears as 250 V in their names; the color is again the last digit. This reading is useful for products whose name does not state the color or voltage.
- EMAS and Gwest: the last letter of the code is the color: K red, Y green, S yellow, M blue, B white. For Gwest models whose code does not state a voltage, it is 220 V; those that say "24V" or "110V" are for that voltage.
Brands in this category
- EMAS: MB monobloc LED, CP and CM contact-block LED, B series contact-block with Ba9S lamp holder and with LED, D series 16 mm round, square and rectangular, H series 30 mm, and S series 10 mm, 14 mm and 22 mm lamps; buzzers with LED.
- Schneider Electric: 22 mm pilot lights with XA2, XB4, XB5 and XB7 codes, rectangular and round with the XB6 code, and 30 mm with the 9001K code.
- Siemens: 22 mm models with 3SU1 and 3SB6 codes, 16 mm models with the 3SB2 code, and 30 mm metal heads; types with plastic and metal front elements.
- Gwest: 16 mm and 22 mm pilot lights with LED, buzzers with LED, and types with voltmeter and ammeter indicators.
Isıso is listed with 16 mm and 22 mm lamps with LED, ABB with compact CL and CL2 lamps and modular parts, and Konsan with 24 V, 110 V and 220 V AC/DC 22 mm lamps.
Ordering notes
- Products are sold per piece.
- You can reach a product directly by typing the manufacturer code (such as XB7EV03BP, 3SU1102-6AA40-1AA0, CL2-523R) into the search.
Panel Pilot Light Color Codes and Voltage Selection Table
| Lens Color / Type | IEC 60204-1 Meaning | Supply Voltage Options | Typical Panel Application | Category Link |
|---|---|---|---|---|
| Green LED Pilot Light (Ø22 mm) | Normal operation / Machine running / Energized | 24V AC/DC · 220V AC | Motor running, system ready or automatic cycle active indication | Pilot Lights |
| Red LED Pilot Light (Ø22 mm) | Fault / Emergency stop / Hazardous condition | 24V AC/DC · 220V AC · Optional integrated buzzer | Thermal overload trip, E-stop latched or critical alarm status | Pilot Lights |
| Yellow / Amber LED Pilot Light | Warning / Approaching limit / Intervention needed | 24V AC/DC · 220V AC | Temperature/level threshold warning or manual/maintenance mode | Pilot Lights |
| L1-L2-L3 Phase Presence Indicators | Presence of incoming 3-phase mains supply | 220V AC (Phase-Neutral) · Door or DIN-rail mount | Main distribution and PFC panel door phase voltage indication | Pilot Lights and Equipment |
Frequently asked questions
What is the difference between an LED pilot light and a Ba9S lamp holder pilot light?
In an LED lamp, the light source is part of the housing or of the LED block, and the lamp is made for a specific voltage. A Ba9S lamp holder lamp takes a bulb or LED bulb with a 9 mm diameter and a single-contact bayonet base; when the bulb burns out, only the bulb is replaced, and the bulb determines the voltage. If Ba9S bulbs are used in an existing enclosure, match the voltage of the spare bulb to the control circuit.
What is the difference between a modular (DIN rail) pilot light and an enclosure door pilot light?
An enclosure door type lamp is fitted into the hole in the door and its front face is visible from the outside; the protection rating is given for this front face. Modular lamps such as the ABB E219, on the other hand, sit in the same row as the fuses and switches inside the enclosure; in the product data they appear as half a module wide and IP20. In addition to single-LED models, three-LED models with 415/230 V AC in their data are also listed. If the indicator is to stay in the circuit breaker row, the modular type is chosen; if it is to be seen on the door, the door type is chosen.
What do IP65 and IP69K mean on a pilot light?
In the IP code, the first digit indicates protection against solid objects and dust, and the second digit indicates protection against water. IP65 means a dust-tight front face protected against water jets. IP69K, in addition to the dust-tight construction, indicates resistance to high-pressure, high-temperature washdown. IP40 and IP50 classes have no protection against water. The value applies to the front face when the lamp is mounted on the enclosure in the manner described by the manufacturer.
Why does an LED pilot light look faintly lit when the circuit is off?
In alternating voltage circuits, capacitive coupling between conductors running side by side in long control cables, or the leakage current of solid-state outputs, can deliver a small current to the lamp even when the contact is open. Because an LED emits light at a very low current, it glows dimly; this is not seen with an incandescent bulb. The cause is mostly the circuit rather than the lamp. The solution varies by circuit; determine the lamp type or additional component the manufacturer recommends for this situation from the project and the manufacturer's data.
Can a 22 mm pilot light be fitted into a 16 mm or 30 mm hole?
It cannot; each lamp is made for a hole of its own mounting diameter. Most products in this category are 22 mm, and 16 mm and 30 mm models are listed with separate codes. When replacing a lamp in an existing enclosure, measure the hole diameter; in a new enclosure, choosing the same diameter as the push buttons makes drilling and spare-part tracking easier. Take the sheet thickness range and the minimum distance between holes from the manufacturer's mounting drawing.