APC AV C10 Design Overview

Spend any appreciable amount of time on the Audioholics website and you will gather that I am a fan of APC AV power products. I'm not so impressed with the name brand as much as the reputation they’ve built over the last couple of decades in the IT world and their talented engineering staff behind the products. I had the opportunity to meet many of the staff during my APC AV On Location visit I paid them two summers ago at their R&D facility in Billerica, MA. Their test facilities are quite impressive which affords them the resources to properly engineer and test their products.

The APC AV C10 Power Filter is based along the design principles of their H15 Power Conditioner but it lacks voltage regulation. Instead it’s a straight up power filter but not a typical one you find from their competitors. This baby’s got some meat on its bones which will surely make the end user happy knowing they are actually buying a device that will do no harm to their equipment while at the same time actually protecting it from dangerous surges and power spikes.

Design Overview

The APC AV C10 is not your typical power filter. In fact, if it was any other company, they would have stamped the words “Power Conditioner” on the product, not gone through the extensive and costly UL certification process, and simply called it a day. APC AV chose the high road here. As competent as the C10 is for surge suppression and noise filtering, they don’t consider it to be a power conditioner. Their definition of power condition is on the same page as mine in that it must meet the three following criteria:

• Surge suppression
• EMI/Noise filtration
• Line (voltage) regulation

The C10 meets 2 of 3 of these requirements. If you want line regulation, you have to step up to an H10 or higher model.

That being said, the C10 is still a valuable commodity for protecting your expensive A/V gear from line transients caused by lightening strikes and power spikes from your local power company. APC AV is so sure of their product that they have a $350,000 life time connected equipment protection guarantee. Anyone can stamp a box with a guarantee but few can back up the safety and reliability of their products with the proper industry regulatory certifications. You will notice quite a few regulatory body approvals stamped on the back panel of the C10 and I will provide a brief explanation to their meaning.

Safety agency approvals: UL1449, UL1363, UL + CSA FCC Part 15 and Part 68 Class B

• UL1449 - Standard for Transient Voltage Surge Suppressors

• UL1363 – Standard for Relocatable Power Taps. A relocatable power tap (RPT) is intended only for indoor use as a temporary extension of a grounding alternating-current branch circuit for general use.
• Part 68 - uniform standard for the protection of the telephone network from harms caused by connections of terminal equipment. What this means is this device can NOT cause harmful interference and it must accept any interference received even if it can cause undesirable operation. The telephone on-hook impedance must be preserved and the line must remain properly balanced so that no hum or added crosstalk can ingress at the customer premise or central office and there is no interference with the telephone ringer.
• Part 15 B - has to do with radiated emissions for commercial usage. Generally, this means the device leaks a signal at some level. Because it costs money to filter out noise, there is always a balance struck between regulatory compliance and perfect filtering in these devices. Microwave ovens or devices with microprocessors may leak within allowable limits but may generate an undesired signal that interferes with something in the way of a licensed communications device such as a radio or phone.

The APC C10 RJ11 phone splitter even includes an REN# (Ringer Equivalence #) which pertains to the electrical load the telephone line sees when the device is connected. 1 REN is equivalent to a 693 ohm resistor in series with an 8uF capacitor. The lower the REN# the better so that it doesn’t interfere with call waiting or caller ID. Most modern phones have a REN# of around 0.2. The APC C10’s REN# is a whopping 0.0 so basically when it’s connected to your phone line, it’s transparent.

Let-Through Voltage

During normal operation surge suppressors are essentially transparent on the line. Once the voltage across their leads reaches their clamping voltage they conduct electricity to create a short circuit in hopes to arrest the surge. They basically give the surge a low resistance direct path to bypass the connected equipment. The clamping voltage of the components in the surge suppressor reveals the most important metric of judging its effectiveness. This is called the let-through voltage. APC conducts this test using a ring wave as opposed to the UL 330V rating which is virtually a useless measure of determining real world protection. Very few companies have this testing capability and most simply create a Joule rating by adding up the specified values of the MOVs in the product. The Let-Through Voltage measurement indicates the maximum amount of above nominal peak voltage the device will allow to reach your equipment after surge suppression. In the case of the C10 which happens to be rated for 40V, this means your equipment would momentarily see about 210V (based on a peak nominal voltage (120V x sqrt(2) + 40V), which is excellent.

Quality Assurance

Every unit ships with Quality Assurance Test Data report marking model#, serial#, time/date tested and the actual tester. In this test they verify full functionality, cosmetics, etc and give status on each tested item a total of 16 tests. Aside from all of the certification and testing APC has done to ensure many years of hassle free and trusted protection, they built this power filter to last. The casing is constructed of sturdy stamped aluminum, all of the COAX connectors are gold plated, the power cord is heavy duty (I’d venture to say 14AWG or lower) with a NEMA 5-15P style right angled plug and the unit has a resettable circuit breaker.