1. What information do I need when deciding on the best power product for my application?
A: Here is a list of questions that can help determine the best power distribution product for a particular application.
1) What is the battery voltage with respect to ground (ex -24, -48, +24, others)?
2) Do you have a preference for breakers or fuses, or a preferred style of fuses (TPS) or breakers ("AM" style)?
3) Do you require a single or dual bus panel? (one or two sets of input cables, each feeding a group of fuses/breakers)?
4) How many circuits do you require per bus (example; 5 per bus in dual bus, so 10 per panel)?
5) What is the amperage requirement of each breaker or fuse (if known) (example; 3 x 5A, and 2 x 15A and 2 x 30A per bus...)?
6) If unsure of amperage's, what is the maximum that you think would be installed in each position?
7) What is the maximum current you will run through each bus (optional, we can suggest from above information)?
8) Do you require battery return terminals (return bar) in the panel or will the returns be connected to another panel/copper bar?
9) What is the width of the rack the panel with be mounted in (19", 23" or both/universal, as well as; flush mount or 5" offset, others)?
10) Any special requirements, such as alarms, size, color, etc?
2. Do I need to ground the chassis for proper circuit operation?
A: Norantel's fuse panels do not need to be chassis grounded for proper circuit operation. But; for safety reasons and as recommended by NEBS (see "9. Bonding and Grounding" and "9.5 Unit Bonding and Grounding" in Bellcore GR-1089-CORE"), it is recommended that you ground the chassis of the fuse panel to the rack or metal enclosure it is mounted in. This will help insure that all metal parts are at the same, safe, potential voltage (AKA, earth ground).
This can be achieved via two methods;
1. A separate conductor (wire) from the chassis to the metal rack or to a nearby rack/safety grounding point.
2. Alternatively, you can ground this small panel to the rack via the panel's mounting brackets, using thread-forming rack screws with tooth lock washers under them to pierce the paint on the brackets. This will help ensure there is a good electrical connection between metal parts.
Either method is fine. Note, our warranty does not require chassis grounding, it is only recommended for your safety.
3. What is the difference between KLM and KTK fuses, and can I use KTK fuses in Noran Tel's KLM panels?
A: The fuses are very similar, both are the same size and are available up to 30 Amps, and are manufactured by Bussmann. Both are widely used in the telecom industry with the KLM becoming more popular as of late. The Noran Tel preferred fuse for our panels is the KLM fuse as it is U.L. recognized and CSA certified for 500 Volts AC and 500 Volts DC. The KTK is only UL listed & CSA certified as a 600Vac fuse (not DC). Due to the DC certification on only the KLM fuse, Noran Tel has chosen to standardize on this fuse and recommend it for use in our 24/48 VDC panels. Note, KTK fuses will work if you choose to use them, but Noran Tel manuals, brochures and stocked fuses will refer to this fuse by the "KLM" part number.
FYI, recently Bussmann has indicated that they have "self-certified"(?) the KTK fuse for 300Vdc. I'm sure that customers will have no trouble with either fuse, but we will continue to offer the KLM fuse as our standard.
Note, neither of these fuses has an alarm indicator pin. Because of this customers may wish to consider our line of TPA fuse panels for new installs. Each TPA fuse can go up to 50 Amps and each has an alarm indicator pin that activates when the fuse is blown.
4. JLE breakers have "LINE" and "LOAD" labeled on the breaker terminals, if the breaker is wired up backwards, will this affect anything?
A: No, it will not affect the operation of the breaker. The breaker will work either way and are tested by UL to insure they work when hooked up in reverse. The only reason the label is there is because the "LINE" side contact is the stationary contact and the "LOAD" side has the moving contact (wiper, etc). So when the breaker is OFF the LINE side will have less energized parts, but this fact shouldn't matter to the customer.
5. What type of lugs are compatible with Noran Tel fuse panels?
A: Please see Compression Lug Cross-reference Information
6. How do I decide what size of wire to use in my panel?
A: Please refer to our Technical Reference section to find the required documents for your particular application.
7. How do I decide what size of fuse to use?
A: Noran Tel recommends using the fuse specified by the equipment's manufacturer. If this information is not available we recommend a fuse that is 1.5 times the maximum current draw of the equipment.
8. What size of BDFB fuse (or breaker) should I use to protect the fuse panel and its internal wiring?*
A: Noran Tel recommends you choose a BDFB fuse or breaker that is equal to (or smaller than) the maximum current rating of the bus you are supplying. If the fuse panel has a bus rating of 100Amps, than a 100 Amp fuse is typically used to protect the bus. In some applications you may choose to use a smaller BDFB fuse or breaker; this is fine as long as this chosen fuse is large enough to supply all your load fuses (the panel itself uses very little power; usually <1Amp). It is recommended that you record the BDFB fuse (or breaker) amperage and fuse location and display this information on or near the fuse panel (the rear shield is a common location).
9. How many output fuses can I install in the fuse panel relative to the bus rating?*
A: The sum of all the fuses installed in that bus must not exceed either of the following parameters; a) the bus rating, b) or the BDFB fuse feeding that bus. In the event you have multiple types of fuses in one panel, you must insure that your installed fuses do not exceed any of the ratings specified in the product manual. Example; 200Amps/Input, 150Amps/TPA Bus, 50 Amps/GMT Bus - please be sure to observe all panel maximums.
10. What does it mean when I see a specification for the maximum current per a group of fuses (example: "150Amps/TPA Bus")?*
A: This rating applies to panels with more than one type of fuse, and it is the maximum amount of fuses (of that type) that can be installed in that bus. In the example of "150Amps/TPA Bus", it means even though it may be physically possible to install more than 150Amps worth of TPA fuses, the panel is only designed to handle 150Amps worth of TPA fuses. In the example, any combination of TPA fuses can be used, as long as the sum of the fuses installed in that bus does not exceed the "150Amp/TPA Bus" rating. If this rating or any other rating is exceeded, the panel may be damaged.
Summary; if the above specifications are followed and output fuses are typically sized at 150% of maximum load (or as specified by the manufacturer), then the fuse panel, BDFB fuse, and cabling will all be typically running at <67% of their maximum rated capacities which should insure a very reliable power source for the equipment. If a fault should occur at any point in the distribution system or the load side equipment, there should be adequate capacity and fuse protection in the distribution system to easily handle the fault without incurring any damage to any of the system components (other than the appropriate fuse).
*Note: When discussing the total fuses installed in a particular bus or panel, we're referring to the sum of the fuse ratings installed in that bus (fuse ratings as printed on the fuse), and not the actual or predicted current flowing though each fuse.
11. Why are the "Battery" input/outputs located below the "Return" input/outputs?
A: Noran Tel feels it is beneficial to have the "hot" or "Battery" terminal on the lower row of terminals. This seems to be the safer arrangement as anything dropped onto the panel terminals would most likely hit the upper terminals, and having a metallic object hit a return terminal would be less destructive than having it touch a hot or Battery lead.
12. Why, on the rear of the panel, are the output circuit numbers labeled from "1 to 10" from outside to inside for each bus, rather than "1 to 10" from left to right?
A: Noran Tel has implemented this feature to aid DC power installers. By having #1 on the outer most terminal on each block and numbering inward for the next output circuit, we feel this would make for easier wiring. With this numbering pattern you would start wiring on the outer most part of the panel and then work your way in. We feel wiring would be easier this way because there will be less wire in the way when you add a circuit as the existing wiring should all be outside of the terminal you are working on.