Frequently Asked Questions

Some of the frequently asked questions (FAQ) about our products:


What is an IP Rating?

It's a quantified measurement of INGRESS PROTECTION of a given switch.
The IP rating will tell you how "waterproof" a switch is, and how resistant it is to ingress of dust.

Handy printable PDF document which gives you tables of the criteria.

How do I connect a specific Cole Hersee part?

Type the Cole Hersee part number in the SEARCH box above and to the right.

Each part has a full description, and frequently a wiring schematic.
If you are still having difficulties, you should consult an electrical professional. Making an improper connection may lead to damage or injury.

How do I find a substitute part?

Type the manufacturer's part number into the search box (above and to the right). If Cole Hersee makes a matching part, the system will take you to the appropriate page.

Note that these are suggested substitutes. Parts are rarely exactly the same. They may differ in construction, design, rating and weight.

Can you explain some of these electrical terms to me?

Check the glossary is the sidebar on the left.

Where can I buy Cole Hersee parts?

Search for a Cole Hersee Distributor by using the FIND A DISTRUBUTOR key at the top right of the page.

For Original Equipment Manufacturers: Check the Cole Hersee Rep List.Our representative will be happy to follow up.

The Cole Hersee catalog rates most of the switches at 12V DC. Can they be safely used in a 24V application?

Sometimes. Items such as Solenoids and Illuminated Switches must be used at the rated current and voltage due to the internal components. Ignition, Push-Pull, Momentary, Door and other types of Non-Illuminated Switches can be used in a 24V system, with one provison. For a 24V application you must de-rate the current capability of a 12V product.

Using Ohm's Law, if you double the voltage, you must divide the current in half. For example, if you have a 12V, 20A product, you can use it in a 24V, 10A system

You cannot use Lighted Switches at different voltages than those specified.

I don't see what I need, can Cole Hersee make it for me?

1. All Cole Hersee parts are designed to be adaptable. For example if the part you see has screw terminals, we can probably make it with blade or wire terminals, or we can connect it to any connector. Such adaptations can usually be made quickly and at low cost.
2. Our engineers are adept at working with OEM engineers to design a switching solution from the ground up. Contact us for more information. 

In both cases there are minimum quantity requirements. We cannot accommodate requests for individual Switches or small lots.

Do you have Switches for my boat?

Yes we do! We have decades of experience in designing Switches to withstand rugged environments. The main factor in determining if a Switch is capable of withstanding the harsh marine environment is corrosion resistance. Steel and salt water are not a good combination! Switches constructed from brass are good for marine use, as are those made of plastic. Many Cole Hersee switches are encapsulated in plastic to give added weather-resistance, and many switches are UL or CE or USCG-rated.

Is there any advantage to screw or blade terminals on a Switch?

If the component is a replacement, try to obtain the same type of termination, because it makes your job easier. Screw terminals require more time to install than blade terminals do, but usually perform better on vehicles, due to vibration.

The catalog shows two Switches that appear to be identical, except that one has a higher current rating. How can this be, and why does one cost more?

A Switch with a higher rating will have more expensive internal components (bronze, copper, silver, and sometimes gold), therefore the cost is higher. Always select a Switch that meets or just barely exceeds your needs. Failure to do so could lead to paying for extra capability that you don't need, or to a Switch that fails if it doesn't meet your specifications. Cole Hersee offers a broad range of Switches in different current ratings to allow you to buy the product that best suits your needs, at the best price.

What is a Packard Connector?

Sounds like something that only fits your granddad's old car, but no. It's an industry standard connector formerly made by the Packard Electric Company (now owned by Delphi.) The name of the connector stays the same though.

Take care: there are several Delphi (Packard) connectors:
Cole Hersee 74600-02 electronic dimmer switch has a 3-pole Packard #298437.
Cole Hersee 95408 ignition switch mates with a 5-pole Packard #2984170.
Cole Hersee 95410 ignition switch mates with a 7-pole Packard #6288702.
We can make all of these switches with any connectors that your heart desires! You just need to be able to order enough so that we can make a batch that's economical for you. Contact us.

Diode Battery Isolators: What is the voltage drop between the center stud (alternator terminal) and the battery terminals?

The forward voltage drop is approximately from 0.7V to 1V (Function of the forward current). For lower voltage drop see Smart Battery Isolators and Combiners.

Battery Isolators: According to the wiring diagram the battery to the "S" must be connected to the primary terminal (yellow wire). What if my alternator does not have an "S" terminal?

In this case disregard this part of the installation instruction.

How is the Battery Isolator current capability defined?

Maximum alternator rating is the maximum charging current capability of the Battery Isolator for both batteries.

What type of Battery Isolator should be used with the Delcotron CS Series alternator?

Use the four terminal Battery Isolator (Cole Hersee 48122, 48092 or 48162). The fourth terminal (#10 stud) is used to excite the alternator. It supplies +12V to the alternator when the Ignition Wwitch is turned On.

What's the difference between the M-412 type Fuse Blocks and the 4622?

The M-412 type is all brass construction while the 4622 has steel rivets in it.

What size breaker or fuse can I use in a 46377 type Circuit Breaker/ Fuse Block?

The Breaker or Fuse should not be rated for more than 25A per Breaker or Fuse with the total of all items used not to be more than 150A.

How do I select the right Dimmer Switch?

If you need a replacement, take a look at the Switch that you already have. Does it mount on or through the floorboard, or on the panel (dashboard)? All floor Switches are SPDT On - On (depress - release for low beam, depress - release for high beam). All are made from corrosion-resistant diecast metal with moisture-repellent insulators. Variations are in the location of the mounting holes, and the nature of the terminals (lead, blade, bullet or screw).

What is the advantage of using a Electronic Dimmer instead of the Rheostat type?

Solid state devices dissipate very little power. They are either fully on or fully off. The power dissipation of a Rheostat Dimmer is proportional to the maximum load current, independent of the position of the dimmer. The energy used to overcome the resistance produces heat.

Electronic Dimmers are not load sensitive. Changing the load (for example by adding or removing a light into a circuit) will not produce a noticeable difference in brightness of a light. Electronic Dimmers are considerably more efficient. There is less loss in the feed cables and substantially less loss (more than 50 times less) in the dimmer unit itself. It therefore doesn't generate a noticeable amount of heat.

Can I use Electronic Dimmers to control the speed of the motor?

No. Connecting inductive loads to dimmers can damage them.

Anti-Restart Ignition Switches - What are they, and where should they be used?

95060 Series and 956 Series Anti-Restart Ignition Switches are regular Ignition Switches with added features. Ever been in your car not realizing the engine is running, and turned on the ignition, only to hear a squealing and grinding of gears? Do it a few more times and you'll burn out the starter motor! The same thing happens with commercial vehicles. Not so much with heavy trucks, where you can distinctly hear the engine running and feel the vibration, but definitely in delivery vans. Often the driver will park at the curb, leave the engine running, make a quick delivery, get back in the van and hit the ignition. Grind! Crunch! Cole Hersee Anti-Restart Ignition Switches prevent this happening. Your delivery van fleet starter motors are safe!

How they work: Most regular Ignition Switches have three positions. 1. Off: key can be removed. Ignition and accessories (radio, lights etc) are activated when the key is in.

2. Momentary Start position runs the starter motor. This position is spring-loaded to return to position 2 once the engine is running. Now if you don't realize the Ignition Switch is in position 2 (you think it's in position 1), you may be tempted to turn it to position 3 (you think you're turning to position 2) with loud and disastrous results!With Cole Hersee Ignition Protection switches the driver cannot turned to Position 3 when the engine is running. (If he wants to restart for some reason he'll have to turn the engine off then restart).This safeguard against burnt-out motors can be retrofitted into any kind of vehicle, such as forklifts or mining vehicles (where the ambient noise is high). This kind of 'lockout ignition' is available with a standard ignition key or with a lever (for off-road applications).

What is the preferred mounting for a Momentary Push-Pull Switch?

They are best mounted on a vertical (or close to vertical) panel. Avoid mounting them on an exposed panel that is more horizontal than vertical.

Can I have a different knob on my Push-Pull Switch?

Sure. We have chromium-plated solid brass knobs in a variety of styles, or plastic knobs. Our plastic knobs all have a metal core that provides a solid connection to the spindle of the switch. You will need to consider shaft size, threads (if any) and symbol or text. See Master Catalog D-275, Section S for knob selection.

What if I need to control one load from two different locations with a Push-Pull Switch?

Use our M-630 Push-Pull Switch. It's an On-On switch. Install one in each location and wire them to control the Off-On function of a single load.

What if I need to mount an SPST Push-Pull switch so that the knob side of the Switch will be exposed to the weather?

Try not to mount it so that it will be exposed to the full force of nature. If it has to be exposed to the elements then the preferred mounting is on a vertical panel, rather than being mounted at an angle to the weather. A Switch such as our 50066 would be a good choice because it has an o-ring in the mounting stem that gives an added protection against the inclemency of the weather.

What is the difference between a sender and a Switch?

A Switch creates a situation that is all or nothing. That is, it allows current to flow or not to flow. The current that flows is not graduated, and is suitable to actuate a pilot light. A sender gives a variable signal of graduated intensity that is suitable to actuate a gauge, indicating a certain level. For example, on a car, a remote Switch operates the 'idiot light' that warns you're about to run out of gas: the sender drives the needle on the gas gauge. Our Temperature Switches have a mechanical contact that is actuated on or off with changes in the temperature surrounding the switch. Temperature senders have a resistive element that varies depending on the surrounding temperature. The temperature sender provides a resistance value to the gauge, causing the gauge to fluctuate.

Do you have other Switches than what are listed in your catalog?

Yes we have hundreds of parts that are not listed.
Contact us to determine the part to fit your application.

Can I have a Pressure or Temperature Switch modified to meet my needs?

In most cases yes, if we do not already have a suitable part in stock. See question 7.

What's the difference between an Insulated and a Non-Insulated Switch?

In an Insulated Switch, the contacts are isolated from the chassis ground or engine block. In a Non-Insulated Switch, the contacts short to the chassis ground or engine block when the switch makes, essentially providing a ground connection to your load. If the vehicle frame is non-conductive, you can't use a Non-Insulated Switch. This is the case with most boats.

Can I use your Non-Insulated Pressure or Temperature Switches with 110V AC?

No. These switches are not rated for 110V AC application. Have a knowledgeable electrician determine suitability for your application.

Can I use your Pressure or Temperature Switches to operate a gauge?

No. You need a temperature or pressure sender. Sorry, Cole Hersee no longer manufactures senders.
The difference between senders and Switches is that Switches are either On or Off, and control a device such as a pilot light. Senders send a continuous variable signal and cannot be used with On-Off devices such as a pilot light.

Can your Pressure Switches handle more pressure than the On/Off rated pressure?

Generally yes. These Switches have an On/Off rated pressure and a higher safe burst pressure. For your own safety your system pressure should be less than the burst pressure. Before you install a Pressure Switch, you should always determine your maximum system pressure first.

Can I use your Pressure and Temperature Switches at 24V?


What types of Solenoids do you have?

You've come to the right place for selection. We have about 50 of them! We have 12V, 24V, and 36V Continuous or Intermittent Duty Solenoids. We have steel or molded bakelite housings. We have plasticized housings for weather-resistance. We even have a Latching Solenoid, which is energized and de-energized by a Momentary Switch. We have an Electronic Solenoid rated at 85A continuous that can be used for voltages from 9 to 31. We have a 200A Continuous Duty Solenoid, rated at 12V or 24V DC.

We manufacture lots of Solenoids!

Can you use a Continuous Duty Solenoid in place of an Intermittent Duty Solenoid?

Always use the component designed for the job. However, yes. You can use a Continuous Duty Solenoid, but it would have a shorter life expectancy compared to the purpose-built Intermittent Duty Solenoid.

But you cannot use an Intermittent Duty Solenoid in place of a Continuous Duty Solenoid!

Do you have UL or CE listed Solenoids?

Oh yes, we sure do! Just search for 'UL' or 'CE'.

How much current does the control circuit in a Solenoid draw?

Generally, the control circuit for a Continuous Duty Solenoid rated at 12V DC draws about 0.70 of an ampere.
The control circuit for a 24V DC Continuous Duty Solenoid draws about 0.34A.
An Intermittent Duty 12V DC Solenoid draws about 2.73A, and the 24V DC about 0.83A.

My Continuous Duty Solenoid gets hot. Is something wrong?

The coil circuit (control circuit) in a Continuous Duty Solenoid is usually energized for long periods of time. Under these conditions the coil will generate heat and within less than an hour the Solenoid housing will become hot to the touch. This is normal. Always make sure that all wiring is properly sized for the load it is carrying, that the terminals are the correct size and have been securely crimped to the wire, that the terminals have the proper torque to the solenoid studs.

Alternatively, you might be able to use the Latching Solenoid that only needs a one-time momentary actuation to stay in the On position.

Are there any special mounting instructions for Solenoids?

Electromechanical Solenoids should be mounted on a non-vibrating surface such as a fender well or firewall. They should not be mounted on a surface that vibrates such as an engine, as this may reduce the lifetime of the component.

Continuous Duty Solenoids should be mounted in an area that has ventilation, as the coil circuit normally generates heat. Our research shows that it might be best to mount the Solenoid dimpled end down. Electromechanical Switches can over time build up deposits due to arcing. By orienting your Solenoid as recommended, deposits will have a tendency to fall to the bottom, clear of the contacts, thus prolonging the life of the Solenoid.

Electronic Solenoids such as 48785 are much more rugged, because they have no moving parts. They also will stand up to an incredible one million On-Off cycles!

What is 'make' and 'break'?

Make and break are terms which apply to any switching situation, but particularly to Intermittent Duty Solenoids, where the buildup of heat can cause failure of the component. Make and break are RATINGS. A particular component, such as a Solenoid, may be rated for duty at a given amperage and voltage that should not be exceeded.

Make is when the Switch (or Solenoid) is turned On (the circuit is 'made'), and break is when the Switch is turned Off (the circuit is 'broken'). Such values would need to be checked with an instrument such as a meter. Note also that Intermittent Duty Solenoids have a limitation on the time (duty cycle) they may be kept On and the time they need to recover (to allow heat dissipation.)

I just installed a 24420 Continuous Duty Solenoid on my road bus. With no load on the secondary contacts, the can runs warm to hot when energized. If this is a normal event, then I have no problem. I always assumed that Continuous Duty Solenoids ran cool, is that not the case?

When the coil is energized continuously the heat from the coil circuit causes the can to run warm to hot. This is normal. Cole Hersee Solenoids No. 24400, 24401, 24402, and 24401-01 are similar, but have two modes of continuous duty service which makes them suitable for forward and reverse systems in some applications. Without the coil energized, the contacts which are closed are rated at 35A. In this instance the can should not run hot. With the coil energized the contacts which were closed open and the contacts which were open close. The circuit that is closed is rated at 85A. When the coil is energized continuously the heat from the coil circuit causes the can to run warm to hot. No. 24400, 24401, 24402, and 24401-01 are commonly used in forward and reverse systems in golf carts, garden tractors, winches, fork lift trucks, and many other applications

Can you give me a refresher course on Single Pole/Double Pole and Single Throw/Double throw?

Check out the SPST/DPST Page...

Can I replace the bulb in any of your Toggle or Rocker Switches?

The bulbs are wired inside the Switch and therefore cannot be replaced. We use a long lasting bulb so that the need for bulb replacement is unlikely in a normal automotive application. We also have LED switches such as 58312 Series that never need replacement.

Can I use your Non-Lighted Toggle or Rocker Switches in 110V AC applications?

Except for Switches M-493, 5507 and similar Switches, none of our Switches are officially rated for AC voltage application. While we are confident some of them can, it is totally up to the end user to determine their suitability for such application.

Can I use your Lighted Rocker and Toggle Switches at 110V AC?

No. The lamps inside the Switches have specific voltage ratings.

Can I use your Lighted Rocker and Toggle Switches at 24V DC?

You need to select only the ones rated for 24V, because the lights function only at the designed voltage.

Can I use your Non-Lighted Toggle and Rocker switches at 24V DC?

Yes. If they are rated at 12V, you must reduce the amp rating by half to obtain the same durability.

Can I get any of your Toggle or Rocker Switches modified to meet my special application?

Yes, in most cases. It is possible we make a suitable item already that isn't listed because of its specialized use. Alternatively, we can make it for you. Naturally we have a minimum quantity requirement for special orders. See question 7.

Do your Lighted Toggle or Rocker Switches have incandescent or LED lamps?

We have both. Contact us if you need a special order with LEDS.

Can I have my company's imprinting placed on a rocker switch?

Yes. Contact us. If it's a standard legend or SAE symbol, there's a chance that it's already available.

What is the difference between dynamic and non-dynamic brakes?

Non-dynamic (coast to park) and dynamic braking or parking refer to Windshield Wiper Switches. Your vehicle has either one of the systems for bringing the wipers to the home or parked position.

If you are replacing a Switch, you need to know which type it is. Consult your Vehicle Owner's Manual.

For those who need to know how they work, read on...

Dynamic brake:
Essentially, when you turn the wipers Off, they stop when they reach their park position, but they also get retarded electrically to bring the motor to a rapid stop. When you turn the wiper switch Off and the wipers reach the park position (left or right), the armature of the wiper motor is disconnected from the load and immediately connected across ground. The motor then functions as a loaded generator and develops a retarding torque that rapidly stops the motor.

Non-dynamic brake:
Essentially, when you turn the wipers off, they stop when they reach their park position. When you turn the wiper switch Off the wipers continue to run by a separate set of contacts mounted on the motor, until the wipers reach their park position. At this point the contacts open, removing power, and thereby stopping the wiper motor. If the motor is not in the park position for the wipers, it continues to run until it reaches the park position and the switch opens as before.

What is the difference between an electronic Windshield Wiper Switch and the Microprocessor Windshield Wiper Switch?

Electronic Windshield Wiper Switches are specific to a type of motor (with or without dynamic parking).

Switches designed to work with dynamic park motors: the PARK wire is blue.
Typical switches:
75600-01 12V DC, controls two motors,
75602-02 24V DC, controls two motors,
75600-02 12V DC, controls one motor, Packard 6-way,
75600-05 12V DC, controls one motor, Packard 4-way,
75600-07 12V DC, controls one motor.

7-way connector Switches designed to work with non-dynamic park (or coast-to-park) motors: the PARK wire is green.
Typical switches:
75601-02, 12V DC, controls two motors, Packard 8-way,
75601-08, same as 75601-02 without knob

Electronic Switches have 7 leads ( 2 red leads). Microprocessor based Windshield Wiper Switches can work with both types of motors. They have 6 leads.
Typical switches:
75600 12V DC, with 8-way Packard connector.
75600-04 12V DC, with 6 wire leads
75602-04 24V DC, with 6 wire leads.