Ample Power Smart Charger Manager (SCM)
Installation and Operating Instructions

Model SCM-12 December 4, 2000
Figure 1 - SCM-12 Wiring Diagram

Ample Power Smart Charger System II
The Ample Power Smart Charger System II consists of a Smart Charge Manager (SCM), one to four Power Supply Chargers (PSC), and one isolator for each PSC. Other miscellaneous options may also be added such as: a shunt for current limiting, a remote alarm, remote switches, or a parallel solenoid.

Mounting the SCM
The SCM is protected against ambient humidity, but must be mounted in a dry location free of moisture, dust and other environmental insults. The SCM will operate in temperatures to 60$^\circ $C (140$^\circ $F).
WARNING: Do not mount the Power Supply Charger(s) or isolator(s) in a closed compartment. Provide adequate ventilation for cooling. Do not place objects around the Power Supply Charger(s) or isolator(s) that will obstruct air circulation.

Wiring Diagram
The wiring diagram above is the only way to wire the SCM. Do not wire in any other way, such as combining ground wires or battery positive wires. For safety purposes, always use fuses where shown.

Signal Names and Functions
All voltages are given for 12-volt SCMs. Double the voltages given for 24-volt models. There are three terminal blocks on the SCM, TB1, a sixteen-pin block, TB2, a six-pin block and TB3, a four-pin terminal block. TB3 is reserved for future use. Refer to Figure 1 for locations of TB1, TB2, TB3, S1, and S2.

Terminal Block 1:

Terminal Block 2 - Optional Remote Interfaces: Terminal Block 3 - Reserved for Future Use:

Configuring the SCM
The SCM is configured by setting two internal dip-switches as explained in the following section. Remove the cover to proceed.

DIP Switches
There are two dip-switches, S1, and S2 on the printed circuit board, as shown in Figure 2 below.

Figure 2 - DIP Switches

The dip-switches are used to select a charge profile appropriate for the batteries in the system and the settings for three current limits. First, select a charge profile by setting the first three battery type switches on S1 according to the following table.

Table 1. - Battery Selector Switches

Current Limiting
Current limiting is used to prevent excess demand from the AC source, for example when running the chargers from a shore connection with only 15 Amps of AC available. With an optional control panel and shunt, current limit can be set manually at any time.

In addition to the remote panel current limit potentiometer option, the SCM provides a means to activate current limiting whenever selected AC appliances are operated. These might be the water heater or air conditioner. To activate current limit automatically when a given appliance is consuming AC power, auxiliary relays are required.

Signals on TB1-15 and TB1-16 are used to activate current limiting which is set on switches S1 and S2. As shown in Figure 2 there are three limit settings, Limit 1, Limit 2, and Limit 3. Limit 1 is activated when TB1-15 is positive. Likewise, Limit 2 is activated when TB1-16 is positive. When both TB1-15 and TB1-16 are activated, Limit 3 is chosen instead of Limit 1 or Limit 2.

Each limit setting uses four dip switches as shown in Figure 2. Limit 1 is set on switches 5-8 on S1. Limit 2 is set by switches 1-4 on S2. Limit 3 is set on switches 5-8 on S2. The switches set the amount of current permitted as a percentage of full scale on the optional shunt used to measure current. Full scale is defined as 0.05 Volts, or 50 millivolts. Table 2 shows the switch settings available for the desired amps percentage.

Table 2. - Current Limit Selector Switches

State Indicator
The green State Indicator shows the charging state of the SCM. Status is shown by flashing the green Status Indicator with On and Off time in seconds as shown in Table 3 below.

Table 3 - Green State Indicator
Status On Off
Bulk Charge 2 1
Gas Charge 6 1
ABS Charge 1 1
Float Charge 2 2
Locked 3 1
ABS Hold 1 3

Error Indicator
Abnormal conditions are reported via the red Error Indicator. Errors are identified by On and Off times of the Red Error Indicator as shown in Table 4 below. If the red Error Indicator is continuously illuminated, the SCM is operating improperly and requires troubleshooting.

Table 4 - Red Error LED
Error On Off
B1 Volts Disconnected 3 1
Over Temperature 3 3
Faulty Temperature Sensor 6 6
Voltage Runaway 6 3

B1 Volts disconnected indicates that the signal on TB2-3 is missing. Over temperature error occurs at 130$^\circ $ F, (54$^\circ $ C). A temperature sensor is declared faulty if readings obtained are abnormal. This error can also be exhibited if the temperature sensor is wired in reverse.

Voltage runaway can be caused by the Power Supply/Charger module(s) ignoring the SCM or from other charge sources that are not controlled by the SCM.

First, look at the Signal Names and Functions section above and make sure that all required wires are in place and properly connected. We have found that moving a wire such as BAT.VOLTS or GROUND a few feet away from a good Battery Positive or Negative Distribution could result in undesirable regulation due to voltage spikes in the system. To help diagnose voltage set-points, remove the T+ (RED) connection to disable temperature compensation and prevent a faulty temperature sensor from affecting the system.

Second, if the problem still exists, obtain a copy of the SCM Troubleshooting Guide which is available from the following sources:
Ample Power Service Center

The troubleshooting guide was designed to help isolate a majority of the installation problems. Fill out the Troubleshooting Guide to determine if all measurements meet the specified requirements.

Finally, if you are unable to remedy the problem, contact the service center with the SCM Troubleshooting Guide completed for referencing.

Advanced Application Information

Automating Current Limits
Figure 3 shows how an AC relay can be connected to a water heater circuit to automatically activate a programmed current limit whenever the water heater is turned on. This can prevent main or shoreside breakers from being overloaded by excessive demand. This circuit is useful for small generators as well.

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Figure 3 - Automating Current Limit Example

This circuit should only be wired by a certified electrician who understands all applicable codes for proper AC wiring. Be sure that relays rated for AC are used. Ample Power dealers sell relays that are appropriate for this application, and include details about relay terminals.

Note the 12-Volts lamp on the signal going to TB1. The lamp assures that the relay contacts conduct enough current to `wipe' the contacts clean of surface films. Such films may not breakdown on the low current draw of the current limit inputs to the SCM.

Activating Current Limit Three
Figure 4 shows how a single relay can be used to activate current limit 3 which requires that both TB1-15 and TB1-16 are driven positive. Any small signal diode such as a 1N4001 is appropriate.

Figure 4 - Automating Current Limit 3 Example

Refer to Figure 3 for wiring that is not shown in Figure 4.

Packing Power Supply/Chargers
Figure 5 shows how to pack power supply/chargers modules in parallel for increased amperage output capability. Note that the modules are connected in parallel with each module connecting to one of the control lines on the SCM.

Figure 5 - Packing Power Supply/Chargers

Stacking Power Supply/Chargers
Power Supply/Charger modules can be stacked to provide 24-Volt charging. A stacking interface module is used. Information about stacking is provided when 24-Volt chargers are ordered.
Click here for the 24V Supplement

Interface to Energy Monitor/Controller
The SCM interfaces to the Energy Monitor/Controller using the ABS signal, TB1-8. This interface operates exactly as that of the Next Step Regulator. Installation drawings for the Energy Monitor/Controller show the ABS control signal. That signal can be connected to both the Next Step Regulator and the SCM.

Power Supply/Charger Power Requirements
Table 5, below, shows: the apparent power requirement in watts; the power factor, PF; and the recomended AC service amperage rating per unit operated over the full AC input voltage range (90 - 140 VAC).
NOTE: The power requirements can be reduced by using the current limit feature of the SCM.

Table 5 - Power Supply Charger AC Line Power Requirements
Model Watts (Power Factor) AC Service
PSC15-12 375 W (0.7 PF) 5 A
PSC30-12 750 W (0.7 PF) 10 A
PSC45-12 1100 W (0.7 PF) 15 A
PSC55-12 1400 W (0.7 PF) 20 A

Ample Power products are manufactured by Ample Technology, 2442 NW Market St., #43, Seattle, WA 98107 - USA