Help with electrical wiring/power consumption. (1 Viewer)

[Jon G.]

I'm hoping Brucek or one of the other resident experts can help me.
I've just killed my 2 Earthquake Cinenova 3 channel (3 x 300) amplifiers. I sent them to Earthquake for repairs and got a call from the chief engineer who yelled at me and told me that by hooking the amps up to my surge protector I'd choked the amps' internal transistors. He was adamant that in the future I plug his amps directly to the wall.
My situation is I rent one unit of a duplex. The duplex's power comes from one line on the street into a master fuse box that has 2 30amp fuses (one for each unit).
My fuse panel is inside our garage. It has 2 15amp and 2 20amp fuses. All the living room plugs and the bathroom light/plug is fed by one of the 20 amp fuses.
In the living room I have:
Mitsubishi 46807 rear-projection tv
Outlaw 950 pre/pro
Toshiba DST-3000 high def receiver
Denon 3800 dvd player
Sony svr-2000 TiVo unit
VCR
Xbox
Playstation
all plugged into a Tripp Lite line conditioner
Tripp Lite specs:
http://www.tripplite.com/products/pr...?productID=211
Output VA / Watts -- 2400
Nominal Voltage / Frequency -- 120v / 60Hz
Input Voltage Range -- 87-140V
Output Voltage Range -- 106-132V
Cord Length -- 6.00 ft. / 1.83 m
Outlet Quantity / Type -- 14 NEMA5-15R (2 front, 12 rear)
AC Surge Suppression -- 1440 joules
EMI/RFI Suppression up to -- 80 dB
Front Panel LEDs -- 5 LEDs show incoming voltage status
Dimensions - H x W x D (in.) -- 5.25 x 19 x 5
Form Factor -- Standard 19 inch rack mount format using 3 rack spaces (3U)
Material of Cabinet Construction -- Steel
Shipping Weight -- 27.00 lbs. / 12.25 kg
Product Warranty -- 2 years
Into the surge protector I had the 2 Earthquake Cinenova Grandes' (powering Paradigm Studio 40s and a Studio CC)
Earthquake Specs:
Number of channels: Three (3) discrete monaural blocks.
Power rating per channel
(8-ohm load), all channels driven: 300 watts.
(4-ohm load), all channels driven: 600 watts.
(2-ohm load), all channels driven: 1000 watts.
Frequency response measured at 1 watt with +/-0.1 dB: 20 Hz to 20 kHz.
Channel separation: greater than 95 dB.
Maximum input voltage: 1.9 volts.
Input impedance: 27,000 ohms.
Total harmonic distortion -THD:
1 kHz, 8-ohm load: 0.001%.
20 kHz, 8-ohm load: 0.003%.
1 kHz, 4-ohm load: 0.003%.
20 kHz, 4-ohm load: 0.006%.
1 kHz, 2-ohm load: 0.005%.
20 kHz, 2-ohm load: 0.006%.
Signal to noise ratio:
@ 1 kHz, 112 dB.
@ 5 kHz, 111 dB.
@ 10 kHz, 110 dB.
High-pass / low pass variable filter, range 20 Hz to 5 kHz (one/ channel). High-pass/Full range/Low pass operation via 3-way switches (one switch per channel).
Dimensions: 9.25" x 18" x 21" (height x width x depth).
Gross Weight : 119 lbs.
On another plug I have a Hsu Research VTF-2 subwoofer w/ 150 watt internal amp.
Other than that, there are a 3 lamps (each w/ a 60 watt light bulb) and the bathroom appliances (3 60 watt light bulbs and my wife's hairdryer) on the line.
Am I way over the limits of the 20 amp circuit?
When I get my amps back I'm going to replace the 2 outlet wall socket with a 4 outlet wall socket and plug the 2 amps and the line conditioner into it.
Unfortunately, ripping apart the walls and installing a dedicated circuit for the amps is out of the question (I rent). Anything I can do short of that? Help and suggestions are really really appreciated. I know next to nothing about electrical engineering, and I can't break these amps again.
I also have a Tripp Lite UPS unit that's supposed to provide a constant perfect sine-wave. This unit isn't currently used, but could be added to the system or used instead of the line conditioner if that'd be a better solution.
Specs:
http://www.tripplite.com/products/pr...m?productID=28
Description Online, double conversion UPS system for freestanding tower or 19 inch rackmount applications (uses only 2 rack spaces).
OUTPUT
Volt amp capacity 1000
Watt_capacity 800
Output voltage regulation On line UPS operation keeps output voltage within 2% of 120VAC at all times. Maintains full battery charge when line voltage is between 85 and 138VAC (60 to 138VAC at loads less than 70%)
UPS supported outlet quantity/type 6 NEMA 5-15R
INPUT
Input connection type NEMA 5-15P
Input cord length, guage 6.00 ft. / 1.83 m
BATTERY
Full load runtime 6
Half load runtime 18
Battery recharge rate 4-8 hours
SURGE
AC suppression response time Instantaneous
EMI / RFI noise suppression Yes
PHYSICAL
Shipping weight 62.00 lbs. / 28.12 kg
Dimensions (HWD) 3.5 x 17.5 x 17 (in rackmount configuration)
Battery access User Accessable, Replaceable
COMMUNICATIONS
Network monitoring port quantity Built in DB9 communications port support RS232 and contact closure messaging for use with PowerAlert software and cabling.
Software and cabling included Includes PowerAlert Plus software and monitoring cable
TRANSFER
Transfer time from lline power to battery mode Zero
Low voltage transfer to battery power 138

 

[GeorgeTW]

The equation for Power is:

Power = Current multiplied by Voltage
1800 Watts = 15 Amps X 120 Volts

1800 Watts is the max you should have on a 15 amp circuit.

Check the UL listings on all your electrical hardware/appliances/refrigerator, etc. and total them up. If you have constant use, close to your max value, then consider moving something to a differant circuit.

 

[Blake R]

I would not recommend loading any branch circuit at 100%. A safe operating margin of at least 25% should be maintained. This would be consistent with the National Electrical Code. I would not load a 15 amp circuit higher than 12 amps. It might be a good idea to get an amprobe and check each of your circuits for actual load.

 

[Jon G.]

Yeah, I'll get an amprobe and check the circuit. Which model should I get? I don't have a circuit breaker panel, I have one of the old fuse-box style panels, with 4 fuses screwed in, 2 15amp fuses and 2 20amp fuses (one of the 20amp fuses powers the living room plugs).

Which amprobe should I get?

 

[Jon G.]

Ok, just got home and took a closer look at the circuit box.

on the inside cover it says:

4 circ.
1 0 3 wire (that's a greek phi letter in between)
30 amp
125/250 volt

The #1 a #2 slots have 15 amp fuses screwed in

The #3 slot has a wider thread (15 amp fuse would be too small) w/ a 20 amp fuse screwed in

The #4 slot (which feeds the living room) has the same size thread as the #1 and #2 slots, but it has a skinny 20 amp fuse screwed in.


Anything suspect about this?

 

[GeorgeTW]

The greek phi letter stand for 'phase'. What this tells me, you have one phase of a 30 amp feed into your side of the duplex. The other leg is going to your neighbor.

 

[Chuck Kent]

Jon: A 15 amp fuse should be on a #14 size wire and a 20 amp fuse should be on a #12 wire. If they are this way, they are properly protected. (You may need someone knowledgeable with wiring to look at this.)

As Blake notes, you shouldn't put more than 75 or 80 percent of the 20 amp maximum load on that circuit. If the wire into your living room is indeed #12, 16 amps max is it.

You don't need to buy an amprobe if you don't want to. Just find the rated wattage consumption of each piece of gear plugged in on that circuit (lamps and all.) This will NOT be the rated output wattage into your speakers etc. Look on the back of each piece near the power cord. Each one will either show the wattage it consumes or the amperage it uses. What you need to do is convert the wattage to amps and then add all of the amps up. (amps = wattage / 120 volts)

I have a feeling that you're going to run out of amps (or be at the max.) If you do, you have 2 alternatives. Rewire the living room AND the apartment feed, or reduce the amperage load by going to equipment that doesn't use as much. This is no equipment you can buy to get around this. The more load you put on a circuit, the higher the drop in voltage that is going to occur. This is probably what the Cinenova guy was refering to. The old addage that you can't shove 10 lbs. into a 5 lb. sack certainly applies.

I wish I could give you a rosier picture. Good Luck!

 

[GeorgeTW]

I agree with Chuck.
You might try is to use more efficient bulbs. Those self-ballasting, spiral-shaped flourescent bulbs sold at Walmart, only use 25 Watts, but are brighter than your 60 Watt incandescent bulb.
You could also advise your wife not to use the dryer whilst watching T-2.

 

[Blake R]

Jon,

The only thing suspect about your load center is that it's standard residential wiring design, which means it's going to be woefully inadequate. Going to more efficient lighting will help a little but the appliance and HVAC loads are still the bulk of usage in any home.

Good luck.

 

[Jon G.]

Thanks for your replies.

I'll check the gauge of the wire this weekend, but it sounds like I'm pretty much screwed.

I guess my options are sell my amps and processor and get a receiver or convince the landlord to let me pay to get a new line into the duplex and have it rewired (what's that run, $3,000?).

I'm really surprised more people don't have similar problems. Does everyone out there with amps have dedicated circuits?

 

[Chuck Kent]

Jon: I'm convinced that some people do have "issues" in their systems related to overloaded circuits but are fortunate in that they aren't serious (re: equipment breakdowns or safety hazards.) Insufficient voltage can affect power supplies and power supplies help to create every part of our setup's image and sound outputs.
I don't think that many user have dedicated circuits. But most don't have the serious amplifiers that you have either (I know I don't :frowning: ) This becomes much more of an issue when you move up to this level of performance.